my phone has been acting crazy. it deleted everything. all these texts have killed my battery. >> michelle sent a flurry of reassuring texted friends and family. i'm fine, she wrote. just taking it easy. so that ex-boyfriend texted her back. his phone number he knew almost as well as her own. a response from michelle. who is this. oh. >> when we come back, did michelle really sent that text? >> coming up -- >> i had asked, is it possible she could just be out there, all stressed out. they said yes, it's possible. but soon, questions about michele's friends would leave police closer than they knew to the key to this case. when dateline continues. case case when ...surprise parties. aww, you guys. dupixent helps prevent asthma attacks... ...for 3!...