i don't know but i think it's worth checking out. it may be something simple like a clogged pore but then again it could be a symptom of something else. because it's a new symptom and not something you expect in a five-year-old it definitely warrants an appointment with your pediatrician. i wouldn't worry too much about this. just make an appointment and get this checked when you can. wishing you the best!
my 5 year old daughter has a pimple that started on the top of her vagina. there are 2 more on upper thigh. what is it?