Cat Picky about food?

My boyfriend just called me and told me that my 1 year and 2 month old cat doesn't eat too much. Since the cats live with him, andi don't see them too often, i have to take his word for it. We co-own them i guess. I pay for them and he cares for them... although his familiy gets in the way alot...

so i have 2 questions-

Question 1:
* "Munchkin" the cat described above, has a medical hisory from a short time ago when she was a kitten, to 3 days ago when she underwent a surgery to see what was causing an obstruction in her intestinal area. The doctor (who is a friend of mine) said that it wasn't a F/B (Foreign Body) or a blockage. She had been throwing up her food 2 days prior. Okay back to the question- after she gets off of her current Eukanuba low Resadue Vet diet in a few weeks, should i comply to her need and feed her some other food?

Question 2: His parents have two 6 month old kittens that live in a different section of the house but my cats - my tux as well "Tai"- eat their friskys food because the doors are left wide open, making my cats frequently sick from the constant switch of food. In my opinion, i would only feed a stary cat who was in dire need of food the foods that their cats are getting, but WHAT CAN I DO TO ASK THEM TO STOP GETTING MY CATS SICK BECAUSE OF THEIR LACK OF KEEPING DOORS SHUT?

SO are there any people who could help me at all? Please help! I hate hearing that my babies are sick!

You aren't always going to get an answer within 5 minutes time especially later at night...but I don't know how you could go about this problem with your boyfriends family. I know your own parents don't like cats, you live with them I assume? Can you just talk to them? I mean, you are a vet tech so you know all about cats and how to care for them. It's not like they would have to think you wouldn't be responsible for them...

As was mentioned in your other thread about what to do; can you buy the better food in large bags and furnish it for all the cats to eat?

I know Chicken Soup For The Cat Lovers Soul is not an expensive quality dry food and 1 large bag would feed 4 kits for a long time.

I dont' believe that 4 kits cost much more to feed than two so if you are purchasing all the food for yours it really wouldn't cost much more to get for them all and then you could be assured what food your cats are eating.