18 month old has yellowish hands... still eats some baby food on occasion... is that what it's from?

Beta carotenemia: Yes this is a typical age for toddlers to have continued yellowish color to the skin from carotene in the diet. Take a look at the whites of his eyes and try should be white rather than yellow. If his eyes look at all yellow, bring him in for his 18 month check and ask your pediatrician about it. Best of luck!

Carotenosis: Yellowish discoloration of the skin, particularly of the hands and feet of infants and vegetarians, is a relatively common finding in people who frequently eat orange and yellow colored vegetables. It is sometimes confused with jaundice, a type of liver condition associated with abnormal bilirubin metabolism. Unlike jaundice, carotenosis is not dangerous and usually improves with time.