My almost 6 month old kittens have been eating less frequently lately (about 2 times per day, 10 hours apart). Does this mean the are weaning off their kitten schedule of eating 4-6 times a day, or could they have an underlying problem? They are otherwise acting normal. The amount they are eating is about 4 oz. each per day. They used to eat about 6 oz each per day. They are 5.5 and 6.6 lbs.