G.B.
I think you are really nice to think of her, if she was not going to be here so close to her birthday then you might be able to get away with not doing something...I think if you ask the BIL what he thinks, is she on FB so you can see what her likes are?, maybe she has some hobbies or collects something, I collect mice and that is what a lot of people do for me when they don't know what to get. I get lots of mice Christmas decorations from Hallmarks collections. Anyway, that's what I would do if I found myself thinking of getting someone that is family a gift for the first time.