I have tragic news to share about Spooky Jr.
I just found the angel, deceased, beneath some bushes in my side garden. I saw him about 2 days ago, and when I approached him he took off, as usual, back to the den site. What appears to have happened is he got his leg snagged beneath an exposed root. It's been so hot and I've been so busy with the kittens, I haven't been spending any time in the back yard. Could I have saved him? I don't know that I ever would have spotted him - and really don't know why I looked under that bush, this morning.
I am in gutted and tears are flowing. Had I grabbed him, that morning, he would still be with us but I just didn't want to traumatize the siblings and mother, and with the new kittens, I had NO place to put him. My brother is bringing a crate by, tomorrow.
I've given him a burial by one of the peony bushes and will come up with some sort of a memorial, once I stop crying.
I have to accept that I can't save every feral I see, but I'm wracked with the most aching and painful guilt, right now. I'll snuggle the kittens with extra love, today.
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At least you found him. It's so sad, don't really know what to say, wish I did.
As you said, you can't save them all. I would be devastated too.
I hope you are able to recover from this sorrow soon. 
It's difficult to care for ferals, especially kittens, but you did the best you could.
Haele
I’d be in tears, too.
found a trail of dead puppies. Many were malformed. One named squeaky made it overnight, but he too passed. Apparently our dog had a uterine infection, but my mother always felt guilty that those puppies were out in the hot sun so long. The truth is neither she nor you were at fault.
I've never heard of a kitten getting caught like that; there's no way you could have anticipated it.
But I can feel your grief from here.
The reason I grabbed a feral litter and trapped the mom several years ago was that I heard one of the kittens screaming, ran outside, and saw a giant raccoon racing off with it. I chased it, but it was too late.
The rest of the kittens, and even the feral mother, all have good homes now, but I still think of that kitten often. He was my favorite, the most outgoing--which is probably why the raccoon was able to grab him.
I try to shrug it off and tell myself I did the best I could, and that very few living creatures are lucky enough to die of old age.
I have cared for a feral mom cat for 7 years. In that time she had 4 litters, all of them made their home in my garage. This spring I had 12 feral cats and kittens, that I loved and cared for.
I considered them and the occasional visiting ferals my family. In less than 3 weeks I lost all 12 of them, and the community cats that stopped by for a meal from time to time. The new grain elevator about 3 blocks away put out rat poison, something they had never done at the old elevator. I still have a hard time spending time in my kittenless yard, crying for my lost outdoor fur babies, so I understand your pain. Loss of those special kittens is part of being a caregiver for ferals. At this time there are no feral cats in my rural neighborhood, but if any show up, there will be food, medical attention, and a place for them in my garage this winter. It's what feral mom cats do. Blessings for you and all who care for feral fur babies. 
A whole cat colony gone.
I don't know how I would get over it.
Please don't feel guilty. You have given your ferals so much help and love, but you can't save them all from harm.
You were doing everything in your power to make sure all the kittens were taken care of. Nobody could have seen this coming.
I'm very sorry to hear about the loss of Spooky Jr. A burial near one of the peony bushes sounds like a perfect spot for this sweet angel.
R.I.P.
It sounds like you did all you could. Please don't blame yourself.
but thanks to good hearted people like you you are saving some of them.
it’s so sad to lose him that way! Poor baby!