I recently started feeding my cat Blue Buffalo, and she likes it
so much that just scarfs it down and ends up throwing it up. She had never had that problem before, but I hated the idea of switching her to something different since it's such a good food and she enjoys it so much. I bought her one of the automatic timed feeders- it has five slots, but the ability to turn it up to nine times a day. It's the only way I can ensure she gets the right amount (a certain boyfriend of mine tends to overfeed her) so she can't overeat. You have to fill it once a day, which isn't so bad. Tell your dad to just set an alarm clock for the same time every afternoon, and when it goes off he knows it's time to fill the feeder.
Here's the feeder I bought from PetSmart:
http://www.petsmart.com/product/inde...ductId=2751315
What's your dad feeding your cats? I think another reason my cat started throwing up is because the pieces of her new food are pretty small, so she just swallows them without chewing. If they're small pieces as opposed to bigger triangular, star, etc. shaped pieces he may want to consider switching.