Help chewie with his surgery

Chewie has had a hard life he came from a puppy mill and developed a liver issue, recently he had surgery for kidney stones and isn't recovering well he's been in and out of the vet over the last 2 weeks spending the night on several occasions because he wouldn't eat or drink.  We are hoping he is on the mend now but he will now be on several medicines for sometime now. Any small amount will help I just want to be able to continue to give him the necessary care he needs. Even if you can't help just please say a little prayer for him.