have clued everyone in that this wasn't an actual elf. gnomes probably do. go ahead and stop no matter who is in the crosswalk. how about that? as a matter of policy, don't duck your responsibilities as driver and just yield to the ridicu-list. that does it for us. cnn special report "buried secrets: who murdered the mcstay family" hosted by randi kaye, starts now. >> there's the house. >> this is the house? >> reporter: once a cold case. >> whoever did this to the family had this well planned out. >> reporter: a family of four vanishes from their home in suburban san diego. no signs of a struggle. >> don't go anywhere without the

double stroller. >> reporter: or any apparent plans to flee. gone without a trace. >> there was no way they left willingly. and it's been said since day one. >> reporter: then four years later, 100 miles from their home -- >> 911. what are you reporting? >> i found what looks like part of a human skull. >> we're able to identify the adult victims as summer and joseph mcstay. >> who brutally murdered the mcstays? a year ago we followed a tragic trail gone cold. >> who is so cold blood that they killed children? >> missed opportunities. dead end clues. interviews with those closest to the family, like this man, chase merritt. then a concerned family friend. >> in your gut, what do you

think happened? >> i have absolutely no clue. >> reporter: now arrested for their murder. >> the cause of death was determined to be blunt force trauma. >> he's in custody. >> reporter: tonight, his exclusive interview and haunting words. you were the last person he saw. >> i'm definitely the last person he saw. >> reporter: who is this man and why do police say he killed an entire family? we take you inside this chilling case. "buried secrets: who murdered the mcstay family?" from day one, i just had this gut feeling that i was never going to see them again. i just -- i just knew.

something told me i wasn't going to see them again. >> reporter: four years ago, patrick mcstay lost everything he loved. four years ago, his son, joseph, daughter-in-law summer, and their two little boys, 4-year-old gianni and 3-year-old joseph jr. vanished. >> i don't think they knew what was coming. i really don't. >> reporter: how did you find out that they had gone missing? >> friday i tried calling him. couldn't get him. sunday i tried calling him and couldn't reach him. now i'm getting a little worried. >> reporter: worried since patrick says he rarely went a day without a phone call from his son. >> every time i talk to him, the last words out of my mouth before we hang up the phone, i love you, son. >> reporter: if he was in trouble and had the ability to reach out to you, do you think he would have called you? don't you think he would have?

>> oh, absolutely. >> reporter: this case is unique. i've never seen anything like it. >> reporter: freelance investigative journalist steph watts has followed the case closely since the beginning. >> they just literally disappeared and nobody noticed for days. >> reporter: thursday, february 4th, 2010, began as an ordinary day in the mcstay home. >> that morning i spoke to joey on the phone. >> reporter: he didn't let on that anything was wrong in your last conversation? >> no. nothing was wrong. everything was fine. >> he had to quickly wrap up and get out of the house because of a lunch meeting. >> reporter: summer was home with the kids, overseeing their home renovation. did they have any plans for that weekend? >> yeah. they had little joey's birthday party scheduled for that saturday, the 6th. >> go! >> reporter: but little joey jr. never made it to his 3rd

birthday party. instead, the family of four left their house after dark that thursday evening, two days before the party. the doors locked, the family car, gone. >> reporter: at 7:47 pm, the neighbor's video surveillance catches the suv leaving the home. it appears, from what we learned, that they left quickly. >> reporter: their two beloved dogs, bear and digger, left outside without food or water. >> i know bear, the big one. and let me tell you something, that dog is like family. summer, that's her -- that's like a kid. one of her kids and there is no way -- >> reporter: they would never have abandoned them like that? >> god, no. >> reporter: food was also left out, eggs rotting on the kitchen counter, coffee grinds scattered about. >> as if you took off really fast but were coming back. >> reporter: joseph mcstay's

mother. >> your thoughts are going wild. why would they be missing? something's not right here. >> reporter: it's a mystery that has baffled investigators. san bernardino sheriff john mcmahonand his investigators are in charge of the investigation. did you have any thoughts of what would make the mcstays leave their home in such a rush? >> at this point, no. why would they take their children, who are 4 and 3, out of the home at 8:00 at night? it's dark. what was it that got all four of them out of that house? and out of that house in a hurry? >> reporter: were they forced to leave or did they leave on their own? early evidence pointed the investigation south to mexico. >> law enforcement was convinced that the family had gone over to mexico willingly at this point. >> reporter: but patrick mcstay was not. so he launched his own

investigation, from his living room in texas. how many hours a day are you investigating this? >> whenever i'm awake. >> reporter: which is most of the time. patrick hasn't gotten a good night's sleep in nearly five years. do you think if he was having a problem or someone would have been threatening him, he would have told you? >> i thought he would have. but i found out later that apparently he didn't. >> was this random or was this extremely orchestrated? and, as the pieces begin to come together, it's looking to me like it was extremely orchestrated. we have to ask ourselves why. >> reporter: why did the mcstays leave their home on a moment's notice and why would anyone want this beautiful, young family to vanish without a trace? shocking clues that police say connect this man to the mystery, when we come back.

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you'll never know unless you go. i did it. you can too. ♪ >> and the boys are on the swing. whoo-hoo. >> reporter: in the months before they disappeared, summer and joseph mcstay's lives appeared picture perfect. >> wee! >> they certainly didn't look like they had any plans to vanish. >> i'm having so much fun. >> reporter: joseph's younger brother, michael, says they had it all. >> everything is going good. two beautiful boys. at the beach. >> wow, it's pumping, guys. >> reporter: everybody loved

joey. the boys were full of life. summer was a great mom. >> reporter: they were living the american dream. joseph worked from home, building his custom water feature business. chase merritt worked with joseph and considered him a close friend. >> he was incredible. he was -- joseph was probably one of the nicest people i have ever met. he loved summer to death. he would do just about anything for her. >> reporter: while joseph worked hard, summer raised their sons. >> taking a cruise on the beach. up there on the cliff. >> they loved the beach. summer loved the beach. joey loved the beach. >> reporter: joseph's father, patrick. >> they had problems just like anybody else. the thing that came down to, they loved each other. >> reporter: macguyver was joseph's closest friend and roommate. he knew summer through his work in real estate and introduced her to joseph back in 2004. >> it was love at first sight

for joseph. my joke with them was pace yourself. i didn't want anybody hurt here. >> reporter: gianni, their first son, was born in 2005. and less than two years later, joseph jr. arrived. >> summer wanted the best for her kids. she was very protective. let me tell you, don't mess with those kids. she's just a very protective woman. not afraid of anybody. >> reporter: shortly after joey jr. was born, joseph and summer got married in a small intimate ceremony in orange county, california. melissa geller was one of summer's bridesmaids. >> she looked so beautiful. it was a great day. it really was. >> reporter: but their marriage wasn't perfect. >> i know summer was very jealous, very, very jealous of, you know, obviously the first wife. >> reporter: in his early 20s,

joseph married a woman named heather. they had a son together. >> she was the love of his life. and when they broke up, it just broke his heart. >> reporter: heather and joseph's young romance broke down after six years of marriage. she filed for divorce in august of 1998, citing irreconcilable differences. >> he would have done anything and everything but, you know, things happen and out of it, you know, the decision was made that, you know, they're going to be good parents together. >> playing with your brother. >> reporter: joseph and heather agreed to shared custody of their son, jonah. >> he loved jonah. >> reporter: when joseph married summer she welcomed jonah into their new family with open arms. >> i remember her helping him make a lemonade stand. she was totally embracing it. >> reporter: chase merritt

remembers something very different. we first spoke to him in january 2014. now, accused by authorities of murdering the mcstay family, then he was pointing fingers in other directions. >> summer hated the idea of joseph spending time with jonah and taking time away from his other two boys. >> reporter: did she like jonah? >> i can't say whether she liked him or not. she didn't act like it. >> reporter: merritt claims joseph simply put up with summer's controlling behavior. >> joseph loved her to death, you know. he thought she walked on water. >> reporter: he also thought she may be the root of his mysterious health issues. >> extreme dizziness, nausea. he went to the doctors several times. they couldn't find anything wrong. >> reporter: merritt says joseph wondered if his own wife may have potentially been poisoning him. >> somebody had told him that maybe he should stop eating at

home. >> reporter: did he truly believe that maybe she was trying to poison him? >> his statement to me was, you know, maybe i should take heed. >> reporter: what would be the reason or motive that summer would ever consider poisoning him? >> we never talked about that. >> reporter: do you believe that summer may have been looking to poison your son? >> i suspected the same thing in the beginning because of joey's illness and everything else. so i went down that same road, you know and, no, i don't believe it. >> reporter: up next, exclusive insights into the day joseph mcstay and his family went missing. you were the last person he saw. >> i'm most definitely the last person he saw. down. we'll even buy you out of your contract. so you can get the samsung galaxy note 4 for zero down today. [laughs]

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>> we got together. we had a lot to talk about. >> you were the last person he saw? >> i most definitely am the last person he saw. >> reporter: chase merritt has never talked on camera before about that day. he met with joseph on february 4th, 2010, to talk business. and business was booming. >> we had 500 waterfalls coming up, the biggest project we had ever done. >> a project, in all, worth about $9 million. after lunch, merritt says they spoke on the phone a handful more times. records show that joseph's phone called merritt's at 8:28 pm. >> i had already talked to joseph 12, 13 times that day and

we had already met for a couple of hours, you know. and i was tired. >> reporter: do you regret not picking up that call? >> hindsight is 2020. sfwlr it was the last known call from joseph's cell phone. the call was made 41 minutes after a neighbor's security camera captured the mcstay's white isuzu pulling out of the mcstay's cul-de-sac. >> did he make that phone or did somebody take joseph's phone and make that call or was he trying to call for help? >> the next day i called him, he didn't answer. i started getting concerned by the end of the second day. >> i put the initial word out to his friends and family that he had been not been communicating online or via phone and i couldn't get ahold of summer either. >> reporter: dan cavanaugh, who had worked with him on managing

his website, contacted patrick. >> my gut instinct was not really a good one. >> reporter: patrick called his younger son, michael, who lived near joseph. >> i need to you go down and check on your brother. again, i get, i'm too busy. >> i didn't want to overreact. we thought that maybe they did a little ten-day vaca. >> reporter: finally on february 10th, six days since the family went missing, law enforcement was notified. >> they don't go into the house. they only check outside the house. at that point they thought there was nothing suspicious. >> reporter: chase merritt told us he was the first person to go to the house to check things out for himself. >> he wasn't there. the truck was in the driveway. dogs were in the backyard with no food, no water. there was a shed to the left of his house that i had built for

him a few weeks before. and it was closed. so i ended up opening the door and held it open with a bucket or something. and i took the dogs dog food, ripped open the bag and put bag inside the shed so that they could get in. >> did you look around the house, see anything suspicious? >> i walked around the house. i didn't see anything suspicious, you know. they just weren't there, you know. they didn't answer the phone. >> reporter: did it surprise you that the dogs were outside? >> very much so. so much so that i called susan, joseph's mother and told her, you know, there's something amiss. >> my mom said chase just left here. he just drove by swroey's house. i'm talking with chase every day. >> reporter: you felt like you had eyeballs on the house? >> i felt like i had eyeballs on the house. merritt told me he was more

alarmed than mcstay family members. what seems to be missing to me is any sense of urgency to find out where they were. >> and that's exactly -- that's exactly what i thought also. i don't even know if i called the sheriff's department if they would do anything anyway. i'm -- to them i'm just a friend. >> reporter: then on february 13th, nine days had passed and still no word from the mcstays. that's when michael decided he needed to drive to his brother's house himself. chase met him there. and, together, they climbed inside through an unlocked window. they found the house in utter disarray, rotten food on the counter, popcorn on the futon. clothes thrown all over the place. >> i don't remember a great deal of it because i was in the house for maybe three minutes, i think. i mean, not very long. i told michael at the time, you should probably call the sheriff's department.

and his response was simply, you know what? let's wait until the end of the weeken weekend. >> san diego sheriff has a rule anyway. after ten days they automatically send out homicide. >> could you have called police and gotten some action before those ten days? >> i don't know. i don't know. maybe. >> reporter: monday, february 15th, 11 days after the family went missing, michael called the sheriff's department, who came to the house to investigate. they immediately alerted homicide. then investigators did something patrick mcstay finds unbelievable. >> they don't put any tape on it, crime scene tape, notices on the door, nothing. they lock the house back up and leave to get warrants. >> it took san diego investigators four days to obtain the warrants they needed to complete a full search of the home. but during those four days, the

mcstays' home remained unsealed. which allowed joseph's brother and mother access in and out of the house. >> i wouldn't go in there unless i called the sheriff's department and they said i could. i had permission. i cleaned up the kitchen because it was disgusting and the trash can from diapers sitting there all that time. >> no, it was not deemed a crime scene because there was no sign of forced entry. there was no signs of foul play at the house. >> reporter: michael says investigators gave them the okay to remove some items from the home. >> with their permission i grabbed his computer, what would be joey's computer and the sd card. i got the pictures off, got that downloaded and then i had to put that back prior to them issuing the warrant. >> reporter: back in texas, patrick could hardly believe

what was going on. >> first thing i'm thinking is like you're going to destroy evidence? i was just stunned. >> certain items that might have been really key to the big mystery why they left that house are gone. moved. cleaned up. it's ridiculous! >> reporter: and as you'll see more roadblocks will soon hamper the investigation. coming up, mysterious surveillance footage and a trail of clues that lead investigators in the wrong direction. so i can reach ally bank 24/7, but there are no branches? 24/7 it's just i'm a little reluctant to try new things. what's wrong with trying new things? feel that in your muscles? yeah... i do... try a new way to bank, where no branches equals great rates.

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>> there's the house. >> this is the house? >> reporter: november 2009, months before they vanished, the mcstays moved into a new house. >> there's the entrance. >> reporter: it was a new beginning. >> light colors. do you like all this big room in here? >> for them to be able to run and play outside, it was perfect. >> reporter: but by february 15th, 2010, that once perfect

house was now shrouded in mystery. the mcstay family was still missing. and so was their truck. detectives send out a be on the lookout, bolo. what did they discover? >> instantly, randi, they get a hit on the truck. it's been impounded from a shopping mall near the mexican border. >> reporter: detectives say that four days after the mcstays disappeared, their white isuzu trooper was parked and subsequently towed from a parking lot steps away from the mexican border. >> there was nothing in that car to indicate that anything bad had happened. >> reporter: now apparent foul play. they had to consider the possibility did they park their car and vanish into mexico?

>> summer was afraid of mexico. would summer take her two children in there? heck, no! >> reporter: but the truck wasn't the only evidence leading investigators south of the border. soon after they found the isuzu, detectives uncovered another clue. a search on the mcstays' home computer from a week before they disappeared. >> somebody at the mcstay home had searched for get iting passports to mexico. >> reporter: then just weeks later, what appeared to be a major break in the case. >> authorities are poring over security tapes from border checkpoints. >> new video could show the family crossing the mexican border. is it the mcstays? >> reporter: this surveillance footage showing what appeared to be a family of four crossing on foot into mexico february 8th, the very same night that the mcstays' isuzu trooper was found

near the border. >> we're getting a story that we found the car at the border and found a family that looks like them walking over the border so they may have left voluntarily. >> reporter: while detectives pursue that family, those who knew the mcstays insisted those people in that video were not the mcstays. >> i told the detectives in no uncertain terms, that is not joseph. >> reporter: why didn't you think it was them? >> joseph has a very distinct walk, number one. he walked like a duck. and the man walking across the border was walking normally. >> reporter: so they're up there, meeting with detectives. >> reporter: fearful that detectives were chasing dead-end clues, patrick called tim miller, a fellow texan, who he hoped could refocus the search for his family. >> patrick sounded pretty distraught.

>> reporter: miller founded the nonprofit search and rescue organization, texas equusearch. he traveled to california, weeks after the family disappeared. >> you know, it was basically a recon trip to look at the area, kind of map things out. >> reporter: miller needed some help. so, he called investigative journalist steph watts. the two had worked together on previous missing persons cases. >> oh, no. he has got one now. >> reporter: their first stop, inside the mcstay home. joseph's brother, michael, let them in. >> very strange. >> what's strange? >> i thought we were going to get in trouble for interfering in a police investigation, for contaminating some evidence, but michael said, no problem. you can be here. >> detectives just told me that this is not a crime scene and i can do whatever i want.

>> baffled me that this was not a crime scene. it baffled me that they even let me in here. >> there's no clues here, is there? >> none. >> reporter: those miller and watts failed to find any evidence of foul play, what they did find suggested the mcstays never planned to run away. >> the double stroller is here. they don't go anywhere without the double stroller. >> the kids' two little laptops. >> reporter: miller and watts left the house that day more convinced than ever that something very bad had happened to the mcstays. so the following day, they drove to the border, looking for areas along the way that appeared suspicious. we retraced that same drive with miller. when you look at such a vast area, did you realize what a challenge you had ahead of you? >> i told michael, we've got a real challenge. it's only going to be a miracle. >> we did believe for a while,

we had a strong reason to believe that they had traveled to mexico. >> reporter: jan caldwell is with the san diego sheriff's county department. >> we had a guy in mexico that thought he served them. someone else had brought them cocktails and we did have sightings. now were they still there and we didn't know? >> reporter: and as more time went by, detectives say the leads dried up and the case went cold. >> it's almost impossible to work a case without information flowing in. >> reporter: the san diego sheriff eventually handed the case over to the fbi in april of 2013. but still, no answers. >> there's some real problems. there were some things that were really missed. >> reporter: up next, the mystery only deepens. a tragic discovery in the mojave desert. were you surprised that the

remains were found in this desert in victorville? >> yeah, actually, because i live -- >> nearby? >> yeah, probably. >> reporter: would you ever suspected this is how it would end, in the desert like that? >> in the desert? i had no clue. r mouth often fee? a dry mouth can be a side effect of many medications. but it can also lead to tooth decay and bad breath. that's why there's biotene, available as an oral rinse, toothpaste, spray or gel. biotene can provide soothing relief and it helps keep your mouth healthy too. remember, while your medication is doing you good, a dry mouth isn't. biotene, for people who suffer from a dry mouth. i lost my sight in afghanistan, but it doesn't hold me back.

i go through periods where it's hard to sleep at night, and stay awake during the day. non-24 is a circadian rhythm disorder that affects up to 70% of people who are totally blind. talk to your doctor about your symptoms and learn more by calling 844-844-2424. or visit my24info.com. do solemnly swear that i will support and defend the constitution of the united states against all enemies foreign and domestic... ♪ ♪ ♪ i thought it'd be bigger. ♪

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i'm happy. it's medicare open enrollment. have you compared plans yet? it's easy at medicare.gov. or you can call 1-800-medicare. medicare open enrollment. you'll never know unless you go. i did it. you can too. ♪ 911 emergency. what are you reporting? >> hi. i found what looks like part of a human skull. >> reporter: the call came in at 9:58 am, november 11th, 2013.

a motorcyclist off-roading in the mojave desert. >> what's the location? >> so you're in victorville? >> yes. >> reporter: a remote area, over 150 miles from the mexico border. >> it's not an area where we would generally patrol. >> reporter: local sheriff's department found two shallow graves and four skeletons. >> through the use of dental records we're able to identify the adult victims as summer and joseph mcstay. we believe the other two sets of remains are that of the boys, their sons. >> it gives us courage to know that they're together.

>> we did it. >> who is so cold blooded that they killed children? >> it was a spot not far from where chase merritt lives. >> reporter: were you surprised that the remains were found in this desert in victorville? >> yeah, actually. because i live in esperia. >> reporter: nearby? >> yeah, probably 20 miles or so. >> reporter: i mean, is this ever -- would you have ever suspected that this is how it was going to end, in the desert like that? >> in the desert? i had no clue. >> reporter: but the police might. the remains might provide crucial leads. >> now we have a scene. >> reporter: we met jan caldwell of the san diego sheriff's department days after the remains were discovered. >> hopefully now that we have a scene, that's going to tell us the answers to this mystery. >> reporter: a mystery once considered a missing persons case now officially a murder investigation.

almost four years since the disappearance, grieving family and friends criticized the initial investigator, san diego county sheriff's department for overlooking evidence that might have helped them find the mcstays sooner. >> i could have probably hired some boy scouts and done a better job. >> reporter: allegations that we put to the san diego sheriff's department in one of the rare interviews they gave on the case. >> this is an incredibly thorough investigation. thumbing through it i can see phone records, photographs, communication. and to have done all of this, to compile this kind of massive file and still not know the answer, enormously frustrating. >> reporter: investigative journalist steph watts and others believe law enforcement was so convinced that the family went to mexico that they missed clues that might have had them searching in another direction, an allegation the san diego sheriff would not comment on. >> common sense did not come

into play here with investigators. why would they have parked a car and walked over? why would they not drive over the border to enjoy a day in mexico? why walk over the border in the dark at night when there's really nothing on the other side at that time of night to do with small children? >> reporter: consider the timing. according to the sheriff, the empty mcstay isuzu was found between 5:00 pm and 5:30 pm at the mall. yet the surveillance video at the border is time stamped 7:00 pm. >> tell me something. where were they for an hour and a half? now with all these cameras in the parking lot, in the mall stores and on top of the bank right in front of where the isuzu was parked, there's no video. >> of them? >> of anything. no video, period, of any of it. that's amazing. >> whoever put that car there fooled us all. that's exactly what they wanted us to believe.

park it close to the border and believe they went over to mexico. >> reporter: even days after the bodies were found, san diego sheriff's department stood by their belief that the mcstays went to mexico. >> did they actually cross into mexico? we still think there's a strong possibility that they did. >> reporter: on november 15th, 2013, the san bernardino sheriff, law enforcement for the county where the remains were found, took over the investigation. >> the first step is getting up to speed on what was done in san diego. there's nearly 3,000 pages of typed material. >> reporter: patrick mcstay still hopes to find answers. >> i'll give san bernardino all the opportunities in the world to solve this case. >> reporter: he has been in contact with the new investigative team to help find out who did this and why. >> it has to be somebody that hated them for a reason.

some crazy reason. and so that person killed them all. >> reporter: cracking a cold case. finally announcing a suspect, when we come back. huh, fifteen minutes could save you fifteen percent or more on car insurance. everybody knows that. well, did you know genies can be really literal? no. what is your wish? no...ok...a million bucks! oh no... geico. fifteen minutes could save you fifteen percent or more on car insurance. we'll even buy you out of your contract.alaxy note 4 for zero down. so you can get the samsung galaxy note 4 for zero down today.

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this is the first time patrick mcstay has seen the shallow graves where his family was buried. it's april, 2014. >> when we hit the dirt off the pavement. >> yeah. >> first thought in my head -- what were they thinking coming up that road? they had to know it wasn't good. >> yeah. >> that's -- that's the part that -- that i don't want to think about. i miss him. >> all he can think about, how his family was killed and who did it. there have been so many theories. a drug cartel. a random intruder. or even a lover scorned as chase

merritt told us in january of 2014. >> joseph was a little bit c concerned about a possible affair summer may have been having. and then there were still no official suspects. have you ruled any one out? >> we have not ruled anyone out at this point. >> reporter: almost everyone we spoke to over the past year told us they met with investigators at one point or another including the last person to see joseph mcstay alive. chase merritt. >> what did they ask you? >> do i know anything about them disappearing? did i have anything to do with it? >> reporter: you took a polygraph test, what did it show? >> i don't know. >> reporter: you passed the polygraph? >> apparently. after i took the polygraph test law enforcement has the not contacted me. >> reporter: do you think you were a person of interest?

>> well i was the last person who saw him, so of course i was a person of interest. >> reporter: did detectives asked you if you killed joseph mcstay and his family? >> i don't recall them asking me. >> reporter: this was then. this is now. >> merritt was arrested, wednesday, november 5th. without incident. charles chase merritt identified as the suspect responsible for the death of joseph, summer, gioni, and joseph mcstay. >> merritt has not been arraigned, select aid lawyer or entered a plea. but he has been charged with four counts of murder. >> to me it looked like a broken man. he knew he was done. >> reporter: we met patrick at his home days after he received a call from the sheriff that merritt was in custody he had been waiting nearly five years for the call. >> a lot of people will say it is like lifting a ton off your

shoalers. i said, no it was more like a boulder falling on me. >> reporter: over the last year, patrick had grown suspicious of merritt. >> it really didn't shock me. >> reporter: you suspected him? >> yeah. especially, the last year since january of this year. we discovered some things that we already had that we didn't put together. we finally put them together. it was like the lightbulbs went off. >> reporter: it certainly hadn't started off that way. >> i was fooled like a lot of people at first. because, i remember my first conversation with joe. about chase merritt. he said, dad, you got to meet chase. he said you will like hip. >> reporter: so you trusted him? >> i trusted him because my son believed in him. >> he was definitely a good friend of mine. weave talked constantly. we played paint ball together all the type. he came down and had dinner with me and my family once or twice a week.

virtually every week. we got pretty close. >> reporter: but as patrick started investigating his family's disappearance, his views on merritt begin to change. >> that's when we found his record. we started finding more out about him. i don't remember all offhand. there was burglary, i think, theft, nothing vie legislator. >> chase handled much of the custom welding work for joseph's booming water fall business. here's what merritt told us earlier this year. >> we were anticipating probably $1.5 million in sales for 2010. that is joseph's total sales. i was probably going to be doing, well over half of those water falls. the majority of his water falls were actually custom. >> reporter: and that was just the beginning. another potential contract of joseph's would bring in about $9 million. merritt stood to make a lot of

money. that is if he kept working for joseph. something that patrick says was in jeopardy. >> the last year, joey had talked about the quality of some of the fountains had slipped. and joey wasn't happy with that. >> blaming chase. at that point. >> absolutely. he was getting complaint. >> was he kidding not doing business with him anymore. >> joey, discussed, getting a warehouse of his own, and getting another welder. >> cutting chase out? >> not cutting hem out. giving him some competition. >> reporter: could it be that simple? could money be the motive? investigative journalist steph watts. >> motives are some times extremely simplistic. money. jealou jealousy. love. lust. it's not that complicated. >> if merritt did do it.

how could he have covered up the brutality of the crime? >> the cause of death was determined to be blunt force trauma. investigators believe these murders occur at their residence in fallbara sfallbrook. >> it is extensive blood spatter. there is no way you could have blunt force trauma without blood spatter. where is the blood? where was the blood in that house? >> merritt told us in january he was at the house days before anyone else went in. and, merritt told us he made sure the shed door was open so the dogs could get to the food inside. seemed innocent then. but now, patrick thinks it was far from it. >> he wanted to keep the dogs quiet. feed them food. water. he doesn't want attention brought by the how. he wants time to go by. which is exactly what happened. >> remember the phone call from joseph's sell to merritt's cell,

one he told us he was too tired to answer. >> how did he know where joey's phone was? >> are you suggestion chase calling? >> maybe calling himself. i don't know. >> reporter: what would be the reason for that? >> nice way to form an alibi. >> reporter: could he have done it on his own. killing four people. and burying all four bodiesen the desert? well, law enforcement believes merritt acted alone. patrick know it so sure. >> reporter: do you believe that one person could have committed this crime? >> honestly, no. i don't bleaelieve that. >> reporter: why not? >> there is just too much there. >> reporter: as the he has done for nearly five years, patrick still waits and hopes. waits for answers. and hopes for justice at last for his family. >> how did you keep up the hope? >> i told you in the first events we did.

i had a gut feeling the first day. i would never see my son again. that never changed. >> new cadillac five. what's up. first bike ride ever? why did i keep going? why did i -- why didn't i fight? one word, joe. >> come on! let's do it! oh. >> nah. >> you are not very patient, are you? >> my son. >> look at you. >> i'm going to got you. >> i love him. and he loved me. >> and i know -- >> oh. >> and i know -- he was saying

you're doing the right thing, dad. i know you'll do it, dad. this is cnn tonight. what an emotional moment. this is cnn tonight. i'm don lemon. you saw the story so far. but the mystery of the mcstay family is far from over. even after the arrest of chase merritt and discovery of the mcstay's body in shallow grades in the desert three years after they vanished. randy kaye has been on the case from the start looking for answers. was some one else involved as joseph mcstay's father believes. what was the motive? will there be justice for joseph, summer, gioni, and joseph jr. randy kaye? where does the suspect, chase meritt say he was