My daughter (nearly 12) is being invited by a boy (12) for a sleepover. It's not like a group birthday party type of thing - it's no one's birthday and she's the only one invited. The boy and my daughter are part of a large group of friends (mostly girls and a few boys) and as far as I know they're just good friends. They boy is a lovely guy and I am friendly with his mum (on a "hello - how're you" basis but don't even know her number). She also seems very nice.
Am I too old-fashioned, as a boy/girl sleepover seems odd to me. What is everyone's opinion on this? Would you be ok with this?