a bossy 9 year old! oh noes!
you don't label your own child, which is great, but you sure slap a quick on young Ava.
i know plenty of single kids who share just fine.
it sounds as if Ava's parents do step in when they find it appropriate to do so.
if you see Ava behaving inappropriately when her parents aren't around, how about saying something instead of just letting it bother you? if her parents aren't there, you are parent in charge. 'Ava, in our house we take turns' is perfectly fine to say.
and i'd certainly tell Miss Lee that she is in charge of finding and creating her own best friends. that she is always free to go to her room and shut the door if she doesn't want to play with Ava but that as Ava's parents are your friends, you, as the adult in the situation, are free to invite them over. it's not all about Lee.
you are not a helpless pawn in this situation, and Lee will learn to be assertive and confident best if she gets to witness you demonstrating assertiveness and confidence instead of handwringing.
it could easily start with you actually having a courteous and forthright conversation with your good and long term friend instead of angsting and prevaricating. 'the girls are going through a sticky phase, aren't they? Lee is feeling the need for a little distance, so let's get babysitters and get together for cocktails next Thursday without the girls. i'm sure they'll be fine soon.'
what you're modeling right now for Lee is that friendships are incredibly convoluted and difficult and maybe she needs to just stick with Ava because look at how hard mom finds the whole thing.
it doesn't need to be so hard. kindness and honesty are not mutually exclusive. telling a friend 'i don't like how you're behaving today. let's play with other people and try again tomorrow' is a great skill for a 9 year AND her mom.
khairete
S.