couch and ross is just goofing around with him and get on the floor with him. and it's hilarious. >> any extra thing that cooper could do, any milestone that he hit, he would share it with everyone. one of the conversations i had with ross, he said that it was so cool that cooper knew his name. and he said, and he loves to yell it at me. so instead of saying dad. he would just go ross. and he would yell ross at him all the time. >> reporter: it was ross who took cooper to day care most mornings. and that was where leanna expected to pick him up on june 18th, 2014. here she is arriving at the day care. >> she got to the day care and cooper wasn't there. >> reporter: leanna called ross to see if there had been a mix-up, but he didn't pick up. and then she had a worrying thought -- maybe ross had