This is such a silly non issue but I can't help it niggling at me and I'm wondering aibu (more than likely) and it's possibly a build up of similar things as opposed to this one thing.
DD (4) has a lovely friend *Adam (6), both only children and absolutely love each other's company. Through the children myself and Adam's mum have become good friends and I really like her but she can be extremely precious over Adam but it doesn't usually affect me.
For Christmas DD got a box set of dvds from a family friend (title 1,2,3,4) and lent Adam 3 and 4 as he hasn't seen them before (DD still hasn't watched either) but last week I got a text from Adam's mum about how much he had enjoyed number 4 and she had gone searching for it but it's only available in the box set, I read it like 
just thinking what a strange thing to text about and thought no more about it. Then when we were out with them the other day Adam was nudging her saying "muuum ask" so she said the same story again about 4 only available in box set blah blah and can he have DD's one and he'll give her one of his old ones and without thinking I just said yeah sure no worries. It was only afterwards I was thinking why does DD have to be the one put out, she hasn't even watched it (probably wouldn't even notice if every one was given away tbh) but it's just like she always gets the short end of the stick and our plans, where we eat if we're on the go, etc always seems to get ruled by Adam mostly because his mum is much more sensitive to his desires being met whereas I'm probably way too easy going and will easily talk DD around to the new plans etc.
I suspect I have pms so go easy I'm probably seeing issue where there is none but it's just all starting to feel a little unfair.