Glad you got it out of the way. It is not unusual for a teenager to invite their mum along to their birthday bash. When my (popular NT) cousin turned 18 she had a big birthday party in a hall that her friends had booked for her, and along with lots of friends she'd also invited her mum, dad and aunt along too. Her dad made all her friends laugh when he'd had a few drinks and got dancing on the dancefloor, and her mum and aunt chatted to some of her friends then left earlier than the others.
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Female