By Kim Glovas

PHILADELPHIA (CBS) — Sentencing is scheduled for September for a Philadelphia man who was convicted yesterday of sexually assaulting his son for two years.

Kevin Willock, 57, was convicted of involuntary deviate sexual interrcouse with a child and related crimes.  The little boy had to move in with Willock in 2004 after the child’s mother was murdered.

The victim testified in court that the sexual assaults began when he was five and continued for two years, until the father married another woman.

Shortly after that, the father and the wife were arrested and incarcerated on unrelated crimes.  The boy testified to a therapist at the age of 11 about the crimes.

The DA’s office says Willock faces a mandatory minimum sentence of 5-10 years in prison but the Commonwealth wants to show that this is Willock’s third strike, which could send him away for 25-50 years.

Willock was previoulsy convicted of several first-degree felony robberies.