We did a sleepover birthday for my son's 7th birthday with 5 boys, most were 6. Went just fine.

I've hosted sleepovers for my 6yo son's friends for a year, with no issues (and one of the friends was 4 at the time). He's slept over at a friend's house twice. I text the moms periodically and everybody does fine, no stress.

Depends on the kids and parents involved. We are the only family in our group of friends who don’t do sleepovers. The kids are between 5-9. My son is almost 7. I’m not a fan of sleepovers in general, but at this age in particular I just don’t feel it’s necessary. Thankfully, my son agrees