sandra whitney is a good friend of alex's parents, becky and mark kogut. she's paige's mom. >> the koguts, they had gone off for a weekend vacation. and they had been texting that evening, and becky was sending her pictures of their hotel room. you know, you get to a hotel, hey look! and alex didn't respond. and she tried over and over again and she didn't respond. and that's not how their relationship worked. you text, you call, you always responded. >> is that unusual, though, that she wouldn't respond in -- in college? it's a weekend. her boyfriend's coming for the weekend. >> i imagine the first couple times, maybe she wasn't concerned. but when it was several -- that's what raised flags with becky. >> was it a little bit of mother's intuition, do you think? >> i imagine it was. >> reporter: alex's mom worked the phone frantically, trying anyone who might know where her daughter was. finally, at 2:42 am, she called the campus police to ask them to go to her daughter's dorm room to check on her. officer michael johnson. >> you took that call. >> i did.

sandra whitney is a good friend of alex' parents, she's paige's mom. >> they had gone off for a weekendn and been texting that everything and becky was sending her pictures of the hotel room, you know, you get to a hotel, hey, look and alex didn't respond. and she tried over and over again and didn't respond and that's not how their relationship worked. you text, you call, you always respond. >> is that unusual, though, that she wouldn't respond in college, it's a weekend, her boyfriend is coming. >> i imagine the first couple times maybe she wasn't concerned but when it was several, that's what raised flags for becky. >> was it a little mother's intuition, you think? >> i imagine it was. >> alex' mom worked the phone frantically trying anyone who might know where her daughter was. finally, at 2:42 a.m. she called the campus police to ask them to go to her daughter's dorm room to check on her. officer michael johnson. >> you took that call. >> i did. >> and you headed over to the dorm. >> yes. >> and then what happened? >> when we went there, i knocked on the door and i knocked twice an