Don’t worry. While it is higher in calories, your two year old is still plenty energetic that it won’t harm him. Even if this continued for the whole year your eleven week old kitten would normally be on kitten chow, he will be all right.

I had a similar situation. My adult cats loved the kitten chow (the same kitten chow they refused to eat when they were kittens), and some of my kittens wouldn’t eat the kitten chow, but liked the adult food. It is years later, and things are fine.
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If you feed a high quality food http://www.petfoodratings.net/cats.html you can feed all your cats & kittens adult food.
The kittens will do better with the adult food than the other way around.
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Retired tech.

Nutrition since there are so many bad things out there is very important to your cat’s health
Contrary to what you may have heard; dry foods are not a great thing to feed a cat.
Please read the label on what you are feeding? What are the ingredients? Do you know what they mean? Is the first ingredient a muscle meat like chicken or meal or other things?
http://www.catinfo.org/#Learn_How_To_Read_a_Pet_Food_Ingredient_Label
http://iml.jou.ufl.edu/projects/Spring04/Perhach/PetFood/InterpretingLabels.htm
Dry foods are the number 1 cause of diabetes in cats as well as being a huge contributing factor to kidney disease, obesity, crystals, u.t.i’s, constipation, and a host of other problems. Male cats are especially prone to blockages
from dry food. Food allergies are very common when feeding dry foods. Rashes, scabs behind the tail and on the chin are all symptoms The problems associated with Dry food is that they are loaded with grains and carbohydrates which many cats (carnivores) cannot process. ( Have a fat cat?)
Also, Most of the moisture a cat needs is suppose to be in the food but in Dry, 95% of it is zapped out of dry foods in the processing. Another thing, most use horrible ingredients and don’t use a muscle meat as the primary ingredient and use vegetable based protein versus animal. Not good for an animal that has to eat meat to survive.
http://www.catinfo.org/#My_Cat_is_Doing_Just_Fine_on_Dry_Food
You want to pick a canned food w/o gravy (gravy=carbs) that uses a muscle meat as the first ingredient and doesn’t have corn at least in the first 3 ingredients if at all.
THE BEST CAT FOODS CONTAIN NO GRAINS NO BYPRODUCTS
Cats are meat eaters not cereal or rice eaters
Fancy feast is a middle grade food with 9lives, friskies whiskas lower grade canned and wellness and merrick upper grade human quality foods. I would rather feed a middle grade canned food then the top of the line dry food.
Also, dry food is not proven to be better for teeth. Does a hard pretzel clean your teeth or do pieces of it get stuck? http://www.felinefuture.com/nutrition/bpo_ch4a.php

Please read about cat nutrition.
http://www.catinfo.org/
http://www.catinfo.org/feline_obesity.htm
http://maxshouse.com/feline_nutrition.htm#Dry_Food_vs_Canned_Food.__Which_is_reall

Vetinarian diets The reason your vet thinks so highly of the pet food they sell probably has more to do with money than nutrition. In vet school, the only classes offered on nutrition usually last a few weeks, and are taught by representatives from the pet food companies. Vet students may also receive free food for their own dogs and cats at home. They could get an Iams notebook, a Purina purse and some free pizza. http://iml.jou.ufl.edu/projects/Spring04/Perhach/PetFood/Vets.htm
Nutritional Education Program website page for the American College of Veterinary Nutrition. Notice who they are receiving grants from for this program
http://mypetcarnivore.com/educational_grant.htm
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