Our friends are holding their daughter’s first birthday at a soft play next month. Our DS will be almost one and the party, at 1-3pm, falls during his afternoon nap (cat nap at 1/2pm ish). When the party is for babies, what is the etiquette - can we arrive late or leave early depending on his nap, or do we need to hack it and face a messed up nap schedule/bedtime that day?