I remember sleepovers at my nana's house. We would be in her bed eating Cadbury's chocolate and listening to fantastic stories from around the world. I loved it. The next day we'd go to a park, play crazy golf, watch tennis and bowling, and eat ice cream wafers. Can't remember how old I was but it was definitely before age 10 yrs old.
Three of my grandchildren stay over every Friday - sometimes 2, sometimes 1. My DGD, who is in year 4, stays every week and has done since she was 3 years old. After gym club we do hot tub then toast marshmallows. We wallow in bed and tell each other about the dreams we've had in the past week, tell funny stories, talk about what we would love to do next. The best thing is marvelling about how beautiful she is while she sleeps. She's such good company and I look forwards to Fridays. Her brothers sleep in the bedroom next to us, when/if they want to stop over. They're younger and fall asleep much earlier.
I have three other grandchildren who have never stopped over because of a combination of distance - if they get upset and want their mum it's a very long drive home, and their own bedroom routine. All three children need a parent with them until they're asleep, they all wake during the night and randomly want their parents/swap beds. DGD who is 5 knows her cousins sleep at mine and she asks to join them but her mum realistically knows that she would be upset and beg to go home at some point. All three children have been traumatised by the fact that mum and older daughter have spent 12 weeks in hospital in the last six months. The admissions have really impacted the bedtime routine and caused separation anxiety.
Saying that I have done quite a few sleepovers at their house on a Saturday so that they can go for a meal and stay in a hotel overnight (birthday, anniversary, bank holidays). I get little to no sleep as we all end up squashed in one bed (super king but small with me and three children, including 2 year old twins, who all appear to spin 360 degrees in their sleep).
All good fun.