How old is he now? Jaundice is very common in babies. Sometimes it doesn't happen right a way. Jaundice is related to the liver. Any yellowing of the skin is something with the liver. But remember everything is connected. The liver filtrates waste products from the blood stream.elevated bilirubin is what causes the yellowish color of the skin. Bilirubin is a yellow waste product of cell function that the liver should get rid of through the bile duct. If there is an issue of the bile duct, it can back up the removal of the bilirubin, which causes the elevated levels, causing the yellowing of the skin.

Are you breast feeding? I've read that jaundice can persist if your breast feeding. I'm not sure why though. It isn't usually dangerous as long as he is eating enough. I would definitely ask your doc about this.

Please don't worry or go reading on the Internet. If you do stick to sites like emedicine or webmd. If he is not vomiting or in any pain, that is a great sign!
That means there is nothing wrong with the bile duct, which could be serious.

Stay calm and listen to the docs.