tonight on "nightline," hooked at birth. newborns detoxing from prescription painkillers their mothers were taking while pregnant. our cameras spend harrowing days and nights on the front lines of a quiet american epidemic with one tiny boy and the extraordinary people fighting to save him. and, stalker 2.0. her tweets gained her hundreds of thousand of online fans. but then, one began making frightening threats and grabs. how this model smokes out the man she says was her cyber stalker and turned the tables on him. plus, the unlikely leopard.

they're sleek, aloof, majestic hunters. well, maybe not this one. meet the filmmakers following one clumsy cat as he tries to make it in the wild. >> announcer: from the global resources of abc news, with terry moran, cynthia mcfadden and bill weir in new york city, this is "nightline," july 11th, 2012. >> good evening, i'm cynthia mcfadden. tonight, a quiet epidemic on the rise for roughly one baby an hour in this country, born hooked on prescription painkiller s their mothers are abusing. they face an uphill battle as we saw when we were invited into special hospital ward in tennessee. abc's juju chang brings us this tale of hope and heartbreak, as part of our division-wide commitment to telling the stories of the invisible among us. a hidden america.

>> reporter: it's noon in the neo natal intensive care unit at east tennessee hospital. and baby grayson is shaking again. >> he's tremoring. >> reporter: grayson was born with a serious drug dependency, because his pregnant mother was addicted to painkillers. now he gets morphine to cut the pain of withdrawal. grayson was brought here from a nearby hospital this special unit for detoxing newborns. right now, there are 23 tiny patients here, going through withdrawal. mostly from prescription pills like oxycontin. it's like their inconsolable. >> people think i exaggerate when i say they have a fearful look in their eyes -- well, they do. >> reporter: carla saunders is the head nurse of this special unit. >> they'll have really bad tremors, really bad jitters. very bad irritability. vomiting, stomach cramping.

>> reporter: "nightline" was given rare access for four days and nights, to witness first hand what they see is a new and hidden epidemic in this country, striking the most innocent of victims. >> when i started, you maybe had a withdrawal baby once in awhile. and then it was once a month. and we have six this weekend, all at one time. it's gone from a drip to a flood. it is a flood. >> reporter: after two days of waiting, there's finally room on the ward for grayson. >> transferring the baby to the third floor. >> he's fairly ji lly jittery. has he needed a lot of tylenol? >> twice today. he's been borderline. >> reporter: it's starting to look like they may begin weaning him off the morphine. this is ashton, grayson's mom. >> doing so good today. so happy. >> big difference from two days ago? >> yeah. >> momma needs you to be more

awake. >> reporter: she says she trailed roxicodone for the first time as a party drug, while still in high school. how easy was it for you to score painkillers? >> they are pretty much easy to find. >> reporter: it's everywhere. >> it is crazy to see how many kids are strong out. >> reporter: ashton says she lost a basketball scholarship to the drugs. having tried to go cold turkey on her own, she knows just how painful withdrawal can be. >> you get cold chills, your skin feels like it's crawling, like it's crawling, literally. you feel so -- you don't want to touch anything. >> reporter: knowing how awful it feels, what goes through your mind when you go that grayson is going through that now? >> it drives me crazy. i mean, it literally makes me, honestly, it makes me beat myself up every day. >> reporter: ashton was trying to recover and on methadone when she got pregnant. but doctors advise pregnant mothers not to stop using, because the baby in their womb

might suffer from potentially lethal withdrawal. it's clear why, when you see grayson now. nurse saunders is helping develop a treatment program using a powerful combination of drugs. it can take weeks, even months for these tiny bolds to withdrawal. >> how is grayson doing? >> still having the jerking tremors and he's got the loose stool. >> reporter: after days of progress, baby grayson suffers a setback. on our fourth day on the unit, saunders still can't wean him off the morphine, as she'd hoped. >> not only is grayson not going to wean tomorrow, i'm going to go right for an increase for him. >> reporter: now, nurse saunders has to break the news to ashton. >> grayson, this morning, was starting to get a little more jittery and he's kind of progressed through the day today. and so, we've had to go up on his medications. i think you can see him

twitching pretty good. >> he's going all crazy, overnight pretty much. just went downhill. >> this is probably the first dip in the roll earl coaer coas. >> okay, buddy. here you go. and this is the increased dose. but this will help settle his jerks down. >> wake up. wake up. open your eyes. >> you are so big. >> reporter: inside the nicu, there are cliglimmers of hope. after 88 days, baby mayson is about to go home. a moment that's bittersweet for the staff. >> you want in on this conversation. i know you did. >> it's okay. you want to tell them about it? it's okay. >> reporter: what goes through your mind, when you hand over a baby that you've taken three months of your life to nurture and care for? >> it's never easy to say good-bye to them. we do get attached.

but we know that we have given them their best shot at the first few days or weeks or months of their life. >> reporter: 3-week-old grayson is one of the lucky ones. his mother says she's try iing keep clean. >> your eyes look a little die lated to maine are you still using? >> i'm still on methadone now, yeah. i have been since -- since i had him. >> reporter: are you using other stuff outside of this? >> oh, no. methadone is the only thick i have used since i got in the clinic. >> reporter: how do you prove that you deserve to take him home? >> you have to start just detoxing yourself. you have to start doing it, just like he's doing it. >> reporter: if grayson could understand what you said to him right now, what would you say to him? >> momma's sorry. it's just hard, i mean -- none of this was planned, you know?

i wanted something better for him, because, i mean, i grew up around it. i know. and it wasn't fun. i didn't want that for him. i wanted better for him, because i wanted to be the mom that i didn't have. >> reporter: for "nightline," i'm juju chang in knoxville, tennessee. >> heartbreaking. as of tonight, baby grayson is still in the hospital, but could be sent home in a week. now, in some states, taking painkillers while pregnant is illegal, but in tennessee, mother and child will be allowed to stay together as long as ashton is in treatment. our thanks to juju. we'll be right back. [ male announcer ] summer is here. and so too is the summer event. now get an incredible offer on the powerful, efficient c250 sport sedan with an agility control sport-tuned suspension.

but hurry before this opportunity...disappears. ♪ the mercedes-benz summer event ends july 31st. ♪ ends july 31st. those surprising little still make you take notice. there are a million reasons why. but your erectile dysfunction that could be a question of blood flow. cialis for daily use helps you be ready anytime the moment's right. you can be more confident in your ability to be ready. and the same cialis is the only daily ed tablet approved to treat ed and symptoms of bph, like needing to go frequently or urgently. tell your doctor about all your medical conditions and medications, and ask if your heart is healthy enough for sexual activity. do not take cialis if you take nitrates for chest pain,

as this may cause an unsafe drop in blood pressure. do not drink alcohol in excess with cialis. side effects may include headache, upset stomach, delayed backache or muscle ache. to avoid long-term injury, seek immediate medical help for an erection lasting more than four hours. if you have any sudden decrease or loss in hearing or vision, or if you have any allergic reactions such as rash, hives, swelling of the lips, tongue or throat, or difficulty breathing or swallowing, stop taking cialis and get medical help right away. ask your doctor about cialis for daily use and a 30-tablet free trial. ...more talk on social security... ...but washington isn't talking to the american people. [ female announcer ] when it comes to the future of medicare and social security, you've earned the right to know. ♪ ...so what does it mean for you and your family? [ female announcer ] you've earned the facts. ♪ washington may not like straight talk, but i do. [ female announcer ] and you've earned a say. get the facts and make your voice heard on medicare and social security at earnedasay.org.

on medicare and social security wheeeeeeeeeeeee! whee! whee! wheeeeeeeee! ah heads up. wheeeeeeeeeeee! everything you love about geico, now mobile. download the new geico app today.to >> announcer: "nightline" continues from new york city with cynthia mcfadden.

>> there's no lack of people trying to make themselves famous on the internet these days, but there's a dark side to online celebrity. cyber stalking. when a model with hundreds of thousands of online followers started receiving frightening messages, she decided to try and uncover the culprit, using, what else, the internet. here's abc's nick watt. >> reporter: kourtney reppert describes herself as a model and online personality. you know, semi-nude photographs and life affirming tweets. she has hundreds of thousands of adoring online fans. >> i always love being in front of the camera. i was like, take a picture. >> reporter: the small town girl from pennsylvania, she's now 26 and moved to l.a. last year. the work's been good? >> it's been great. >> reporter: fame can come easy on this online age, but so can the flip side of such accessible celebrity. e-mails like this that began

arriving march 8th. >> i will kill your parents. i will cut them to pieces. you wait and see. you're all going to [ bleep ] die, you [ bleep ] -- there's more. if my demands are not met soon, i will kill you. you know what my demands are. >> reporter: and his commands were? >> that i needed to stop modeling, delete my accounts, move back home, be someone else. >> reporter: the fbi traced the e-mails to computers in chicago public libraries. a dead end, perhaps, to an increasingly common problem. recently, although cyber stalker was jailed for shooting video of erin andrews. he posted the video online. >> these are people that don't have a lot going on. and all of a sudden, they can pull strings and they can make someone afraid of them.

>> reporter: were you scared this guy was actually going to materialize? >> yeah. i was, like, i'm scared for my life to end, and he, like, changed the way that i view people. >> reporter: reppert's stalker seems to have suffered a dlugs that she belonged to him and no one else. she received nearly 400 threatening messages. >> i hope you die in an automobile accident and it crushes your ugly face through the windshield with a large piece of glass and it cuts your throat. >> that's what it was all about with the threats. how dare she? she's not remaining pure for me. you know, she loves me and now she's putting these pictures of herself out on the internet? >> reporter: so why not just stop posting the pictures? >> it's a catch 22. you got to put yourself out there, but this is not something that i asked for. >> reporter: stalkers have been around as long as there have been celebrities to stalk. in 1998, jonathan norman was jailed after he was found at steven spielberg's l.a. mansion

carrying duct tape, a box cutter and hand cups. he told police he wanted to rape the movie director. in 1980, john lennon's stalker, mark david chapman shot the beatle dead outside his manhattan apartment building. >> they put the victim on a pedestal. once they are rejected, it's angle, rage and rejection. and the internet makes it easier. with youtube, with twitter. because these stalkers believe that the celebrities are actually talking directly to them. and there's a lot more information out there about the victim. >> reporter: reppert's stalker knew where she lived, where her parents live and whoho her fries were. she noticed a similarity in style between the vile threats and some is supportive messages posted on facebook. the fbi traced those messages to a man who lives at home with his mother. he's yet to plead after being charged. >> i don't feel safe.

>> reporter: she's teamed up with a former miss usa to start a website offering advice and support to other victims. you do feel better? >> a little. but the damage is done. >> reporter: from 2,000 miles away, he got terrifyingly inside her head. a high price to pay for a taste of online celebrity. i'm nick watt for "nightline" in los angeles. >> our thanks to nick. and just ahead, a clumsy young leopard tries to make it on his own in the wild of africa. last season was the gulf's best tourism season in years. in florida we had more suntans... in alabama we had more beautiful blooms... in mississippi we had more good times... in louisiana we had more fun on the water. last season we broke all kinds of records on the gulf. this year we are out to do even better... and now is a great time to start. our beatches are even more relaxing... the fishing's great. so pick your favorite spot on the gulf...

and come on down. brought to you by bp and all of us who call the gulf home.

he's sort of the black sheep of the leopard family.

not graceful, not agile, just adore bly awkward. he's also now a star of a new documently called "the unlikely leopard." here's my decidedly unclumsy co-anchor, bill weir. >> reporter: the little guy is just 10 days old. vision hazy, balance insteaddy. which is why a newborn leopard's chances of survival are 1 in 6. but his vulnerability is offset by a cuteness so powerful, his mother is loathe to leave him in order to search for their brek fast. she is also young, and he is her first cub, so, she has no idea how he'll fare while she's off chasing wart hog piglets. back in the den, he awakes to find mom still gone and a different kind of spotted creature, one with a distinct height advantage. so, he decided to investigate.

leopards have the unique ability to lock the muscles of their wrists to prevent them from sliding off a tree, but when it comes to climbing, this one is far from gifted. the mother returns from the hunt, the den is empty, her baby cold, but she figures out that for this one, going up is a lot easier than coming down. and it is not just a phase. even at 6 months -- he has not lost his clumsiness. she's still falling, still getting stuck. and the mother is torn. these are largely solitary animals and she has an instinct to move on. but he's still defenseless and she still can't resist the mamma's boy. in bolt bots wana, when this l was found, they knew he would be the star of their next film. >> he was so clumsy and, of course, we were laughing most of the time. we thought this would be a great

film. >> reporter: so, this is more comedy? >> i would say so. >> you get these perfect feline animals, and then you get this one. >> reporter: a farry goers can go years without spotting one. but on a morning drive, we were lucky enough to find a big male casually wandering. >> that's very often the way that we find leopards. you go through here, you hear a franklin calling like that, and it's indicative that there's a leopard in the area. >> reporter: does that bird have anything to fear from a leopard? >> yeah, yeah. we've seen them run around and chase chicks. leopards in this area will kill 33 different species of prey. from mice and skiquirrels, all e way up to young buffalo. >> reporter: but the skin that makes them so invisible to their prey also makes them so vulnerable to their predator. man. in just five years, a quarter of a million leopards were killed for fashion. and only about 50,000 remain.

>> but those are 50,000 individuals that we've been following, great characters, wonderful personalities, like you or us, you know. we each have own our personality and animals do, as well. >> reporter: at almost a year old, this leopard has still yet to make a kill of his own. still plays with the food mom provides, still drops dinner. buff when another big male comes around, he has a rival for his mother's affections and she finally has to push him away. can he survive? can he hunt on his own? the unlikely leopard shall see, but the bigger question, can their work, out here, make hunting animals like this any less fashionable? >> "the unlikely leopard" premieres this sunday, july 15th on nat geo wild. thank you for watching abc news. we hope you'll check in for