Katie,
Welcome to the disgusting world of Irresponsible Pet Ownership. Feral colonies are popping up all over the place because people refuse to get their cats fixed. It's sad, because it's not the cat's fault.
4 weeks is a little young to be separating them from mama. 5-6 weeks is usually when they start becoming more feral and it's time to separate them. But if the only time you can trap them is at 4 weeks, then so be it. And not all feral kitties will come around socially either.
Remember LilA??? She's gone back to Rhode Island and is living with Freedom. I had her for a year (right Sandie??) and no matter how hard I tried, there was still the feralness in her that I just couldn't break.
You are doing a wonderful job and are to be commended. Just remember to take care of yourself too, girlfriend. You don't want to burn out the way I did. 5 words to live by...YOU CAN'T SAVE THEM ALL!! As much as we'd all like to.
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