If you are a dad, date your daughter. If you are a mom, date your son. What I know to be true is that if it is important to you how your children will treat their spouse when they grow up and marry. If you are a single parent, see if another close relative that you trust can assist you in this area. You must model the way on how they should treat or interact with the opposite sex. After all, it's the right thing to do and it models the way for others.