We'll probably call the doc if this doesn't go away soon, but any ideas what this could be? She's had her hands in her mouth quite a bit lately, but she also had 4 teeth coming in at once. Our sitter noticed it this morning and said it looks bigger than cold sore :(. Poor girl, I feel so bad that we didn't notice earlier. She's seemed fine lately, but has definitely been sensitive to us brushing her teeth. I thought it was just that she didn't like it! Any experience with your LO having something like this? She's 19 months.

Sorry for the poor picture quality. It was a screen print of a video where she was fussing.