I have trained kittens to use a harness. If you star at a very young age and they have never been outdoors without a harness it is not a problem. Kitten Socialization: Training a Kitten to Wear a Harness. I'll try her way next time :)
Well it seems a little oxymoronish to Kill and be Kind at the same time.but being kind is the right thing to do, maybe instead of killing them they will learn to be kind also, or just be kind in return. The Golden Rule if you will.