would you worry about this? He is nearly 2.1. It is quite small, less than a fingertip. He is well otherwise, and developing normally: talks well and very active and happy. He was born with a (cardiac related) birth defect, which can sometimes be associated with chromosomal issues, but he doesn't have any other symptoms of these. I don't think I would have worried about it at all if I hadn't consulted Doc Google, who as always likes to throw up all sorts of horrible possibilities. Anyone had any experience of this?