We have also learned that just as it is best not to intervene with baby birds or bunnies it is best to leave feral kittens with their mothers in their outdoor homes until the kittens. A low box with a soft blanket in the bottom tucked into the corner of a quiet room can be a great place for your cat to keep her kittens. Bury the kitten into the ground.
Mother cats are EXTREMELY instinctual. Do not reach into the trap with your bare hands and attempt to scoop her up. I brought her home from Pennsylvania about a 4-hour ride and she did really well. They move their young only to places they feel are safe.