There's a whole bunch of sleepover stories on Fimfiction, many of them featuring our favorite filly trio ("Stare Master" has a lot to answer for, it seems). I've always loved seeing and reading about sleepovers, so I thought it was time they got their own group, and with arcum42's kind permission, I'm being allowed to advertise it here:

We've already got a whole bunch of slumbery stories for your reading pleasure. If you're interested, please join, and also suggest stories that I might have missed (we're accepting any story which has a sleepover in, which is probably quite a lot considering the relaxed nature of Equestrian society). Happy Hearthswarming!

3905916 You should promote it in New Groups group.

3906829 - thanks! I was looking for something like that.