Hope little Gracie feels better soon. Our Dylan had an urine infection when he was younger. He was peeing blood. He had tests for crystals and was on a special diet for a few months. I remember the vet saying it is sometimes the infection can stir up the crystals in the urine and he had no bladder stones. He has had no further infections. Though since that time they have always had filtered water we live in a hard water area.
Erica