My situation is a rather strange one. I'll start by saying that we live on a farmhouse (though we don't participate in agricultural activities, my aunt is just letting us stay there) after moving here some 3 or 4 years ago. We brought our spayed house cat with us, but there were already a couple of cats living in the nearby storage buildings. Eventually we found some kittens, and of course, being kittens, we lost our senses around them and started putting out cat food*.

Fast forward several years. There are now at least 15 cats living around our house. I won't try to make excuses, and we did enjoy getting to interact with the different litters of kittens that came along. We're more or less barricaded in our house now. But what's really concerning to me is the way that the latest litter has been behaving. There were originally three, one black, one gray, and one yellow. Unfortunately the gray one recently died after getting stuck between a piece of furniture left outdoors and a wall and freezing, starving, or suffocating to death (the adult cats regularly get into commotions and meow very loudly, so we didn't hear anything out of the ordinary). Even before that, though, we noticed very strange behavior in the black and yellow ones, but especially the black one. When allowed inside (or when they forced their way inside while someone was trying to enter or exit), they would frantically sprint all over looking for food of any kind. When they found some, they would very enthusiastically and intensely (read "ferociously") try to eat it, and if anyone tried to separate them from it, they would do their best to inflict the maximum pain possible - biting and scratching and flailing around.

It sounds like they must be starving and on the verge of death, right? But when this is happening, the food bowls we leave outside aren't empty. Either they're being systematically denied access to the food when we aren't looking or this is just their personality, which I *really* hope it isn't. The black one in particular will start growling and hissing and slashing at the ground in front of him if anything gets as close as about 4 feet while he's eating. Just recently he slashed his sister (the yellow one) across the eye when she tried to get something to eat (it started oozing fluid). We tried eating some take-out dinner in the living room while they were there, and the black one jumped onto my dad's lap, grabbed as much of his sandwich as he could, and bolted away to try to eat it. When I went to pick him up, as usual, he basically attempted to kill me. I had to chuck them both outside.

Further complicating things, I have friends/family who are interested in taking care of those kittens. But I don't know if I could give them such vicious little things in good faith. After they've eaten their fill and been in the house around an hour, they calm down a lot and seem friendly. I'm not sure exactly how old they are, but they are at least a month old, likely a fair bit more. They are big enough that you need more than one hand to hold them comfortably. I believe they have stopped nursing recently.

Many of the cats we used to bring in occasionally as kittens attempt to rush in through the door whenever it opens, and they enjoy their 20 seconds of warmth and then let someone pick them up and set them outside without much conflict. But if the behavior of these kittens continues in this way as they grow, they will be not just a nuisance, but an actual threat to our safety - peaceful adult cats not used to being carried can still inflict deep scratches, a violent adult cat could slit someone's throat.

I am at a loss for how to handle this. I want them to grow up to behave well. I want them to be healthy. None of the other kittens we've had have acted like this. Is this some once-dormant issue caused by the inbreeding? If they truly aren't getting the food we provide, how can we make that so? Our manpower amounts to two full-time college students, plus one depressed mom, minus one dad with alzheimer's. I don't think I can expect our mom (who usually handles the daily feeding) to realistically feed all 15+ cats separately. I've tried some basic conditioning, grabbing them by the scruff when they try attacking my hand near their food and giving them a light bop on the head, but it only seemed to make them reluctant to eat near me (this of course being immediately *before* I looked online and saw that you're apparently not supposed to use punishment on cats...).

Their behavior doesn't match anything I've read online. I've read about food aggressiveness, but nothing seemed this extreme. How can I improve their behavior, or, if a lack of food is the underlying cause, ensure that they get that food?

*: I realize that many responsible pet owners may feel the urge to comment on what horrible and irresponsible people we are, and how we deserve everything we've got. It's not like I didn't know the population would end up growing out of control. But the kittens made my mom happy, so I don't regret it. That is all.