We're all born different from everybody else in the world, human but unique in our own, special ways, made so by the mysterious stew of genetics passed along by our parents. It's what makes us six-foot-two-with-eyes-of-blue, or gives us long, piano-playing fingers, or feet that only fit the least popular sizes of shoes.
While you can generally make some predictions on how a baby will turn out just going by the parents' features and traits, there are still going to be some surprises in store. But nothing could have prepared one baby's parents from a thoroughly unexpected development.