My oldest never had a sleepover - he has autism and wasn't ready, and by the time he was, he didn't want to. My youngest had two sleepovers, both with her best friend, in middle school. They're now in high school and seem not to want them anymore.
All of which to say, we are not a sleepover sort of family

I know other kids, of all ages, who do sleepovers all the time.