I used to work as a forensic psychologist in the courts. I’ve never met a colleague of mine that allows sleepovers during childhood and early adolescence. I don’t either. Aside from my direct exposure through work, I know many people who have experienced abuse or difficult experiences at sleepovers. It isn’t always fathers, it can be from older siblings, or other adult or teenage guests. Being exposed to inappropriate things on the internet is also a factor. When mine were 10, I picked them up around 9pm. I just explained to other parents that we don’t do sleepovers and didn’t elaborate. For DD at that age, I simply said, ‘different houses have different rules, we don’t do sleepovers, because your dad and I sleep more comfortably knowing you are in your own bed, and that’s important to us’. As she got older, the messaging could change a little.
There have been 2 occasions I went to pick her up at 9pm to find the parents hosting the sleepover had had a party with other parents and random adults, and were absolutely wasted. I was SO glad I collected her. That had never been mentioned to me, and there is no way any of those adults would have been able to respond to a sick or worried child at 2am.
Look, maybe my kid will be in a therapists office in 15 years discussing how unreasonable I was about sleepovers, but that seems better than the alternate possibility. I’m actually not a generally strict parent at all, but the research tells us that sexual harassment and abuse is common, and is most likely to be perpetrated by someone known to the child. Once it happens, you can’t rewind time and the child carries that forever. We know the issues that abuse causes, and it’s just one way of reducing the risk.
Stick to your guns, OP, but offer to let her go for the evening and pick her up late. Even if you just fudge the truth this time and make plans for early-ish the next day to justify the decision.