It's proper that rules are applied to everyone the same.
Brian is the coach of his son's pee wee soccer game but his son isn't a good player.
Brian wants his son to be able to play more.
Brian gives his son extra coaching at home, so he can improve his skills and play more.
Brian puts his son in games more often than the other kids so his son has a chance to play more.
Brian's son gets better at soccer and shares a bonding experience with his dad.
The other kids notice Brian's son is getting special treatment and are mean to him because they are upset.