Should I share with my cousin?

We both went to a concert on monday, I took pictures of the artists, and watermarked my photos and placed them on the internet. The thing is i'm going to have the images copyrighted and I don't wnat anyone else to have them. She demanded the pictures and told me that I had to give them to her without the tags on them. [in a jokingly way of course] I told her that I'd give her a couple of pictures but not all of them [there are 84+ total]. I know i'm being selfish but I want to keep the pictures to myself, what should I do about it?