cat has a stone in her bladder

My cat just got diagnosed with a stone in her bladder. I realized it because she was peeing some blood. The vet put her on royal canin urinary SO. Will that help disolve the stone. I need some positive replys because I am so sick about this. She is acting fine. eating drinking some peeing a little at a time . It will cost 1500.00 to have it removed if this doesn't work. Im feeling very depressed. Thank you to all.