>> my sister-in-law used to call every morning. my mother would be on my phone with me and say, oh, i gotta go. diana's calling on the other line. >> reporter: diana was a stay-at-home mom with two kids, leah and harris. peggy doted on her grandchildren and would fly them up to new york to spend summers and holidays. detectives had already confirmed that diana's cell phone had been in washington, d.c., at the time of the murder. but when phone analyst robyn arias looked more closely at diana's calling pattern something seemed off. >> when she was in d.c. her activity was just all over the place. kind of the frenetic feel. there was definitely something going on. >> reporter: now arias looked at who diana was calling, putting names and faces to the numbers on her phone. she noticed diana suddenly seemed have a lot of new friends in washington, d.c. >> a lot of people just popped