My sons refuse to believe me when I say there's no such thing!
When they were small, birthday parties had sugary sweets, cakes, Coca Cola etc, and there was only the behaviour which was normal for children hyped up by attending a party.
When I worked in Early Years, one mother told me to give her son Coca Cola before she collected him, and she would know immediately. I never gave him it, but on three occasions she brought him next day and said she knew he'd had it the day before, as he was more hyperactive than normal!
Husband - so lazy
Step-step kids - how to treat them
Gifts for friends - yes or no?