The Stepmother 5: Her New Son(2011)

Beautiful blonde Tanya Tate is all set to marry handsome divorcee Dale DaBone and move in with her teenage son and his pregnant fiancée. But Dale's ex-wife Magdalene is still bitter about the divorce - and about the new sexy blonde taking her place. Enraged and vengeful, Magdalene sets her sights on Tanya's son Seth, and they begin a torrid affair. When Tanya discovers evidence of their trysts, the busty MILF decides to turn the tables - and pay a visit to Magdalene's sexy son, Xander.