You're getting married in early September. One of your male cousins will have a four month old by then. They were told before the child was born that you don't want any infants at your wedding (In March at your engagement party). You get a call from your cousin saying that they can't find a baby sitter and will need to bring him to your wedding and if that's alright with you.
The cousin is not married to his child's mother, so her family wasn't invited to your family.
edit: It's my sisters wedding. Not mine. She is far nicer than I am.
I would've exploded.