tracy nix says she forgot little uriel in her car seat. but this isn't the first grandchild to die on tracy's watch. >> i can't forgive it. absolutely not. as a father, i can't. >> plus a husband trembling in a police interrogation room. >> why? >> his wife dead from 47 stab wounds. he said she took her own life. cops said he killed her. >> it had to be me for the butler. we didn't have a butler. >> if he's innocent, why did he say this? >> to? >> was it suicide? was it murder? >> did i. >> do it? lord, please tell me. >> thanks for joining us. we begin with the case against a florida grandmother convicted of leaving her seven month old granddaughter alone in a hot car for hours. tragically, the infant died. and it isn't the first time one of tracy nix's grandchildren would die while in her care. tracy nix was more than happy to help out her daughter kayla, when she needed a babysitter. it was a chance to spend some time with her seven month old granddaughter, uriel. but after picking her up and taking her to a prearranged bible group lunch