[Taiki]

If they weren't able to survive out on their own, then you definitely did the right thing. A stray cat that I haven't been able to catch has had kittens in my yard twice already. The first time she had snuck into one our sheds and had them in there and I didn't find them until they were like 2 months old so by then they were really feral and wouldn't get along with humans. I had to take them to a shelter because I couldn't afford to get them all spayed/neutered and time to tame them.

The 2nd time she had 4 kittens I found them when they were 2 weeks old and they were already hissing at me! I didn't want to take them from their mother at that point cuz they still needed milk so I kept checking up on them to try to get them used to humans. However the mother kept moving them and I could only find them like once a week. When they were about 6 weeks old, she had abandoned them. I found only 3 of them near starving to death (the last one I assume had already died because I never found it) and my gf and her brother was nice enough to take them in and feed/take care of them. They're all spayed/neutered now and somewhat tame. 2 of them still act kind of feral but not as bad as the previous litter of kittens.

So anyways, in my experience, if they're out dying, then taking them to a shelter to give them a shot at life was the right thing to do if you couldn't take care of them yourself. Leaving them unattended to go out and have more babies would have been bad.