Sleepover drama. Dealing with mixed gender sleepovers.

I have two kids. A daughter who is 13 and a son who is 12. They are both fairly social kids and like to have sleepovers frequently. My daughter invites girls and my son invites guys, but the kids are get along pretty well and tend to hang out as a group. The girls sleep in one room at night and the boys sleep in another. There haven't been any issues so far.My daughter's good friend recently informed us that she can no longer sleepover if my son is having friends sleepover. Her parents don't like the idea of mixed gender sleepovers even though the kids are separated. The problem we are having is that our daughter is not allowed over their house to sleepover either. The parents don't host sleepovers.My son could sleep at a friend's house to allow his sister to have sleepovers with her friend, but we run into a small issue with our son's best friend. His best friend doesn't have the best home life and normally comes over all weekend to hang out. His mom works a lot and his brother has significant special needs, so attention is devoted to him at home. His mom works overnights and his elderly grandmother comes to watch his brother on the weekends while he comes to our house.I'm not really sure how to handle this. My daughter doesn't think it's fair that her brother gets to have his best friend over every weekend but hers can't stay. I can see her point, but can't think of any other options we have. Am I missing something? Anyway we can make this fair for both kids? via /r/Parenting http://ift.tt/2invUFY