Sorry for the post and run, rl called.
Thanks for replies
I asked because my 2yo and 6yo (dd's 2 and 3) were playing happily upstairs (were being pop stars! ) and it occured to me that I wouldn't have been happy leaving dd's 1 and 2 up there when dd2 was only 2 years old, and I wondered if perhaps I was getting a little too lax relaxed in my parenting.
Seems I'm not, or at least, if I am, then lots of you are too