FarmerBoy24 said:
I think he'll die without my help It gets freezing over here! at night. Im going to keep him as a pet. How will this kill him??
I would suggest you call a rehab for info. My survival rate for wild buns has been 0%. I'm sure you mean well and please know this is not said in a harsh spirit at all, yet, sadly, he will mostly likely die with your help, and especially so after a cat encounter. Even experienced wildlife rehabs have near a 100% death rate under the best conditions. Cottontails cannot survive a pet environment. His best hope for survival is to return him near the known burrow area. He could be weaned already if he's 3 weeks old and the doe probably has a new litter now.