What Could Blisters On Vagina Lips Suggest?

My daughter looks like she has a blister (2 red spots) on the opening of her vigina I plan to seek medical advice, but am worried it could be something harmful. She is only 2 years old. is this normal? I was wipeing the inside of her vigina and noticed this today, I have never had to spread the lips in order to clean that well, but she was playing in a lake today and now I am worried.