My 2 year old daughter has 3 dimples on her butt crack is that normal?

See base? If you can see the base, probably not a problem. She is too young to determine if bladder or bowel continence is a problem, but if concern speak to your pediatrician.
Possibly. Dimples around the lower spine or anal cleft can be normal or signs of an underlying problem. Shallow dimples in the mid line & along the lower part of the anal cleft are less worrisome than those that are vary deep, include a tuft of hair or are located an inch or more above the anus.Point this finding out to your dr.