My 7 year daughter has a rash on the outside of her vagina. what can i do?

You have to be more : Specific with description of the rash to give you better answer. I would presume irritation, dry skin or eczema. Is it just red, is it raised, thick , dry and scaly , does it itch? Are there pus or is there a break in the skin?!? You see what i mean?

Pediatrician visit: She needs to see her pediatrician, asap. It may be an allergic reaction, infection or other causes which need medical attention.