Bear will be 4 months on Feb 4 and is not eating very much. He ways 38lbs and the vet says he should eat right around 3.5 cups of food 2 to 3 times a day. He will only eat maybe 2 cups the whole day and that's pushing it. Is this just a stage or should we be worried he is very active and we exercise him all the time. Is there something we can put in his food to maybe intice him to eat?