What type of rash is this?!

I haven't really noticed until today after my 6 year old daughter had held & kissed her newborn baby brother for the first time that she had this little rash under her bottom lip.😨😨 She didn't even noticed it herself. She says it doesn't bother her and doesn't seem to be in any pain. But I'm a little concern, is her skin like "chapped" or is it because of this weird dry winter? I just hope it isn't something contagious