What's been your experience of kids either gravitating towards kids of the same gender, or not, when they start school? My son's friends at nursery are all girls. They're all heading to the same primary soon and noticed his friends have started to pull towards other girls on our street or want to say "I don't want to play with Harry - girls only!!" recently.
Another mum has the opposite. Her tomboy girl wants to muck around with her mates who happen to be boys, and they're saying she can't play as she's a girl. Is this the type of thing that just happens around age 5?
Would love my son to keep his group but I can see it splintering. He has no proper concept of girls or boys being different in terms of play or games.