I totally agree @Mummybearto3bg I see where you are coming from. I hear clearly that they are really good friends and her DD has always been invited to your daughter's party. I also agree with others who see how hurtful it is to not be included. I am always amazed at how parents allow for exclusion that is obvious and so hurtful. For two years we were at a small primary school and my eldest was at the age where parties were all the girl's in the class. The parties excluded 1 girl (my daughter didn't ever do this) in the class. My daughter thought it was so cruel. This girl was very very bright (genius IQ) and ASD with tics and I always felt that was a big and horrible reason why. When my DD invited her to her party, her Mum actually contacted me to tell me her daughter cried at the invite she was so happy. This girl btw is now sixth form age and highly successful, runs her own business, predicted all A's. Many many friends through her hobbies. A delight.
A similar thing happened to us this weekend @Mummybearto3bg with a friend whose dd I always send a card & pressie to. She actually contacts about 20 of us to ask via email each year to not forget her SEN daughter's birthday. This little girl has significant SEN so she let her make a list of who to invite, and I can see it only included people she's seen in the last month and the dc of Mum's closest friends. She has significant longer term memory challenges so if she hadn't seen anyone in the last month she may not think to say them. Anyway, she and my DD are friends. My younger DD is so kind with her, has helped her with swimming, art, it's truly lovely to watch and my friend always gets teary saying how my daughter sees her DD as an equal and she really does. My dd doesn't define people by their disability and genuinely sees her daughter as a friend. Anyway, hey are having a big party today and my daughter isn't invited.
I am not vindictive so even once I saw what was happening I still bought a really lovely, unique gift i know she will love and sent it. This friend has never once sent my dc so much as a card. But asks every year for something for her dd so she feels loved/cherished/special. For me it's about the dd not my friend. We've invited her DD to parties but she has never come b/c the Mum is very scared of germs. We even had a party outside fully (with tents) in hope she could be included but b/c we couldn't confirm all guests were fully vaccinated, she didn't feel comfortable with her DD attending.
This stuff when dc are close but not thought of hurts and does make you look at whether your dc are taken advantage of by being a friend when needed, and excluded when not. Not a nice feeling and sadly something many parents' orchestrate.
Before anyone says it, yes people have a right to invite who they want. But this is different when a friend is excluded, especially when the friend always includes their dc.