My SIL who I do like is single and in her 40s. She works, has her own flat and is always busy with friends, dating etc.
She loves to be out and about and so quite often if she asks what me and DH (her brother) are up to going to see a film, for a meal, to see a band or a play she'll say oh I fancy that, room for one more?
I don't mind her coming at all but what does annoy me is that their is always this expectation that it will be our treat which makes it awkward when it comes time to pay for things, she's definitely always hanging back in the hope that me and my dh will pick up the bill and is quite put out if asked to pay for her meal, ticket etc. I think it could be that my DH will usually pay for things when we are out so perhaps she feels like she's paying and I'm being "treated" but that money comes out of mine and DHs joint account so I am paying my share!
I got fed up with it and so have started just booking things and keeping quiet about them but she's now gotten upset about that saying she'd have loved ro see that show and we should have invited her. She can be touchy and so I was hoping to avoid a scene with her but will probably just have to say that she can't keep expecting us to pay for her unless it's her birthday or something.
I wonder if she does with her other friends or of its just us, I'm sure it isn't normal behaviour.