I have to disagree that this is normal. I've been caring for kids for 32 years and I've never seen it. My suggestion is to stop talking about it and start blocking it. Put her in a pair of backwards footed pajamas every day all day long until she learns to cope without doing it. If she wears a size three pajamas then buy her a pair of size four. Put them on her backwards where the zipper is up the back. Just rotate the feet forward and zip them up. The one size up will give you the extra material you need to rotate the feet forward. She needs TIME where every day she can get thru the day without comforting herself THAT way. My rule of thumb is that if it bugs me it's not okay. I trust my gut and I don't like ANY kind of fixation so I don't do fixation behavior. I don't like it so I block it. I don't really put any energy into whether it's normal or not. I go by how it makes ME feel. If it tweaks my sensibilities then I know to stop it. Trust your gut.