prosecutors maryclare flynn and katie rayburn understood why. this affects everybody, adults, teenagers. even parents with kids who don't even have phones yet. >> absolutely. i think it's good to be thinking about what you're putting out there in the world because once you send it, you can't take it back. >> turn the gears! >> reporter: prosecutors believed michelle's words and actions caused a vulnerable conrad to kill himself. he described his fragile state in that video diary. >> racing thoughts, suicidal thoughts, and flashbacks of hard times. >> reporter: and prosecutors learned michelle did more than send text messages to conrad. as deadly carbon monoxide filled the cab of his truck, michelle was talking to him on the phone. >> there were two phone calls after the last text message -- one from him to her, 41 minutes -- and then, one from her to him for over 42 minutes. >> reporter: but how would they ever know what was said on those calls? detectives pored over thousands of text messages and they got their answer. >> lo and behold, on her