2nd AIBU of the weekend 
Had a party for my 5 year old today. Lots of people turned up (great) but around 5-6 children brought 1 (or 2!!) older siblings with them. I don’t mind them being there, but the parents didn’t pay for them, and simply added them on to the list at the door, so our bill was over 100 pounds over what it should have been.
AIBU to be really pissed off at this? The invites were to the named child. I know childcare can be a pain, but I would never do this.