DD is 14 (year 9) and was invited to a party tonight. There were about 20 people there and I knew a few of them but not all. DD is pretty responsible and I do trust her. The girl’s parents were not there but her older sister (18 was there) as the parents are away on a mini break. I bought DD some drinks - nothing too intense just some Smirnoff ice and WKD. She came home about an hour ago and was a bit drunk. I personally don’t think this is an issue and I was doing far worse at her age. My MIL (staying for Christmas) on the other hand went absolutely ballistic and said how inappropriate this was. I genuinely don’t see the issue of a teenager going to a party and having a bit to drink. I don’t want to raise my kids to be joyless or uptight and I want them to actually have a good time. Aibu?