S5, E15: The body of a 16-year-old girl is found while Benson (Mariska Hargitay) and Stabler (Christopher Meloni) are chasing down a rape suspect. The victim is Shannon Coyle (Jenna Gavigan) and her grief-stricken mother Susan (Helen Slater) and brother Brian (Spencer Treat Clark) are devastated. She was at choir practice and never made it home. The detectives were having some difficulty with leads and when the choir teacher's prints come up (on a secret key in Shannon's purse), they think he is the suspect. They go to his apartment and find him in bed with Shannon's best friend, Lisa (Stefanie Nava).