pilonidal dimple

My daughter has had a pilonidal dimple since birth, she is 17 now and has had no problems from this in all this time, i have actually forgot about it and she never even knew she had it, but, just yesterday, it started producing blood from it. what we need to know is what do we need to do and what do you think could be wrong. she has had some unexplained leg pains over the last year or two and nothing has been found, could the dimple be part of the reason for that pain.
thanks, a concerned mom, flosi