@tenangsaja I would be pissed and make them stand in the corner (yes even the 12 year old) for a good while.
I would then tell them they get a clean slate.
It's not worth your whole vacation. Do a grounding exercise or something and try to move on.
@tenangsaja If the balcony was low enough for the little one to pee off of I'd be extremely pissed at the 12 year old because that sounds very dangerous.