Former seventies teen idol David Cassidy found out he had slept with the same woman as his father just months before his dad's sudden death.

The Partridge Family star and his actor father Jack Cassidy spent time together on the latter's 1974 touring show, where David discovered Jack was cheating on his second wife Shirley Jones and drinking heavily.

In David's autobiography Could It Be Forever?, he recalls, "What I remember most about that weekend was spending the night with one of the girls from the show, only to find out she had already been sleeping with my dad. When she told h...