kevin was 15 years old when he walked his mother down the aisle. they moved into bill's home on a quiet cul de sac in seminole, florida, near st. petersburg. a solid neighborhood. good schools. for the first time, kevin had a steady male role model in his life. >> so how was kevin fitting into the picture here? >> kevin was fitting into the picture quite well really. he really took to me more than anyone else that diane dated with, she told me that. and, you know, we got along very well. >> reporter: kevin appreciated bill so much, he wanted to take his name. >> he wanted his name to be the same as his mom and i. and i was very proud of that. >> reporter: so, what's wrong with this picture? not much. kevin got along fine with bill, but joining a big family with five kids was a challenge. he didn't always fit in. there was tension, and a lot of it swirled around the new baby of the family, young kevin. >> you could tell he was raised as an only child because he was all about himself and all about his way all the time. >> reporter: but kevin's cousin tanya says the kyne kids didn't make things easy for their step-brother.