Hi, My 3 year old has had a pimple like growth on his buttocks (by his anus) for over a month now. It is only one, on a small scar he has since he was weeks old (the area was once drained after a cyst there was found- they were unable to culture it). The tiny bump does not seem to be fluid filled or hard. It is not red or painful. At first I thought it was a cyst, I thought I saw a tiny black dot on it but it may be my imagination. It appears to have gotten a tiny bit bigger. Should I be worried about a bump that has not gone away?