It might be normal in the chicken world, but reading this made me cry my eyes out, and they are not my precious chickens.
Your Biscuit and her babies were beautiful! I am so sorry for your loss.
One thing for sure, your neighbor should never feed raccoons. Even if they weren't so destructive, they carry rabies and should never be encouraged to come to neighborhoods by being fed. We have had so many rabid raccoons in Virginia this year.
I have been so lucky. I see a red fox in the field in front of my house nearly every day. My neighbor to the rear sees coyotes all the time in the woods that separate out properties. My woods is full of groundhog dens and we have a lot of possums. My run and coop are not Fort Knox by any means, but so far nothing has happened to my six laying hens. I have my seven week old chicks in a fairly secure pasture pen inside of an electric poultry netting fence, but I still worry.
I am having a secure coop built this month, which will have a fenced run, but after reading this, I am going to surround the whole thing with the electric poultry netting fence. It is a pain to get in and out of the electric fence, but not as much pain as finding my my precious babies killed.