The age at which sleepovers are appropriate is 10 years of age and above.
Sleepovers and Slumber Parties are not really appropriate or a good idea for those under 10 years old.
However sometimes my son who is 8 years old will have his 8 year old friend sleepover at our house for a night or two and I know his parents really good and he's a good kid.
But most kids are not ready for sleepovers until age 10 or above.
But some kids may be ready a bit sooner but all the parents must agree on it.
Some kids do not like sleepovers though so if your kid asks someone to sleepover then it's okay if the other kid refuses the sleepover or slumber party invite.
Some kids suffer from social anxiety or they may wet the bed and not want to attend.
Not liking sleepovers is perfectly normal.
Some people enjoy sleepovers and other people hate sleepovers or have anxiety over sleepovers.
I've had anxiety when I was a kid and when asked to go over to a sleepover I would do my best to avoid them and make up excuses to not have to attend the sleepovers.
I myself suffer from social anxiety and have a hard time making friends especially when I was a kid and was very shy and although I had a few friends I mostly stayed to myself.
Staying at others houses can be stressful and uncomfortable for some people and that is okay.
You can simply turn down a sleepover invite if you want too and if they are your true friends they will understand and if they were not your true friends then you'll find out.
I've always been uncomfortable staying at peoples houses including my own relatives and my grandparents house and could not sleep.
I'm not sure why I was uncomfortable at my relatives houses even though I knew them but it was probably the social anxiety because it still happens now that I'm an adult.