My sons is asking for both boys and girls to stay over. One I know will not be allowed as his mum wont even let him go on playdates without her (sad, as it is his best friend) the other I have no concerns with as I know his mum well and we have a set up where we take eachothers children to tennis, to Ikea, on days out for half term (we are both working mothers), so it helps us out and the children have fun. Mostly they are either single parent families, or families with many children, all from my sons RC primary school. The parents are very active in the church, and I hope and believe they have a healthy and wholesome home environment, what ever that means.
I did not start going to, or have, sleep overs till I was around 8-9, and I think that is a good age. At that age a child can wash and brush teeth and get ready to bed without too much adult help, and I too have fond memories of supper time with other families, breakfasts, chatting and playing till late late, and it was all great fun.
Really, it was only stopped by our mothers when as 11 / 12 year olds we started sneaking out of windows to pretend to be ghosts roaming around the neighbourhood dressed in white bedsheets (especially where boys we fancied lived)....