My daughters have played beautifully today (aged 4 and 8, both gifted). I've loved listening to their elaborate cat/vet game. From an observer, I'm really happy with their interaction, their role play, their sharing, their problem-solving about who makes up the rules, etc. And it's certainly not always this good!
But... it's a stretch for Miss 4.5 to play with Miss 7.5. She has to extend herself. Mostly, Miss 7.5 accommodates this because she gets a lot out of the play herself and really enjoys it. But Miss 7.5 is not stretched by the play. I often wish Miss 7.5 could spend time with older girls - role models, kids that stretch her... But this is besides the point and not related to your situation.
I suspect, although could be completely wrong, that your friend may like hanging out with you and your DD but really aspires a "real friend" for her daughter - someone that is her daughter's own age. Do you openly talk about giftedness? Is your friendship with this mum competitive? How do you think she feels to see her DD playing with someone 3.5 years her junior? Does she accept that they're playing at the same level? I suspect not.
Mixed age friendships are very hard - not for the kids, but for the parents. What messages do you think this friendship between the girls is giving your friend? It seems to me that she might think that it's fine for "playdates" but it's not a genuine friendship. And you may need to confront her about this...
jojo
