Hiya, me and my girlf were in the exact same boat, our kitten got ran over and we were devastated, and were contemplating get another because we didnt want to ever have to go through the same again. I always said you cant keep a cat indoors, because i thought it was cruel, but now ive kind of changed my mind to the fact i think it depends on where you live, for roads etc. And after visitng the cat rescue centre, and i saw literally hundreds of cats inside cages the size of a shed, i realised that they can have a happy life indoors if you provide them enough fun and games. My opinion would be to cat proof your garden, it wouldnt take much and if you spend some time on it it doesnt have to look a mess either. Either that or keep the new kitten indoors and give them lots of toys, a cat condo or something like that. I think the garden is the best option though, we try to give pets a close to natural life as possible but whilst staying safe dont we i think thats what cat proofing your garden is.

Hope all goes well x