First sleepover?

My oldest DD is 6 and in kindergarten. She has a friend that’s moving away this summer, and her mom texted me saying her DD was having a sleepover and invited my DD. She’s never stayed the night with anyone other than family. I don’t want to hold her back if she wants to stay the night, but she is very shy and I’m very nervous about it. We’ve talked about body safety rules, but if she were put into a bad situation I don’t know if she’d actually stand up for herself. I know I can be overprotective, my mom was sexually assaulted by 3 different men throughout her childhood and I’m just paranoid about it. I do know the parents a bit, from birthday parties and volunteering in class together. But we don’t know each other that well. When did you let your LO’s stay the night with a friend? What advice do you have, precautions you’ve taken beforehand? via /r/Parenting http://bit.ly/2MefzWr