My 18 mo has been a great little eater until 2 weeks ago when he suddenly decided he didn't want to eat. He literally has no more than 1 bowl of cereal a day, he wont drink milk and is just not his usual bubbly happy active self. I am desperately worried - is this normal ? Last night he vomitted in the middle of the night for no obvious reason and brought up the 1 bowl of cereal he had managed to eat. Any ideas ? I'm hoping for some reassurance.