that is so sweet of you to do. I hate to think of kittens outside and scared.
my girlfriend in Houston has a town house with an atrium and she'd just brought a kitten home to be friends with her 2 yr old cat. worked like a charm they took to each other right away. but a month ago, the kitten was in her atrium and playing with a bat. the animal control came and got the bat an found it was rabid. now she must wait 45 days to see if the kitten shows signs of rabies. they both got their shots after this happened.
so it's difficult to keep even house cats completely safe.