When John's wife decides to go out with her sisters, he suspects that she'll be slutting. Left at home with his wife's daughter, he decides that what's good for the goose, is sauce for the gander.
Michelle was a virgin when the summer began, but like so many teenagers in today's day and age, her curiosity, along with the urges of maturity, began to take their toll. With horny cousins and an equally horny brother, it probably could have been predicted that she wouldn't stay untouched.