My almost 3 yr old was born with quite a large sacral dimple, we saw a paediatrician when she was a few months old who wasn't worried about it and said it would even out as she grew. It is less deep now and has grown into two shallower dips. The other night I touched the area around it and she started to cry saying it hurt and wouldn't let me touch again, it's not red or inflamed and looks the same. She doesn't have any of the problems associated with deep sacral dimples such as weakness or cold feet.
Should I be concerned? See HV or keep an eye ?