My 12year Old GR-daughter Has A Large-maybe 3/8 Inch Almost

My 12year old GR-daughter has a large-maybe 3/8 inch almost hanging lump(?) on outer labia cheek. She had pain while walking today. Upon moms exam, it appears blood red. No head noted. I am an RN, and saw pic of it....maybe a boil? I haven't seen any this large, but I know this is an area. Please help.