How can I remove set-in urine stains from my quilt?

Is the quilt washable? If so toss it in the washing machine, or take to a coin laundry and pre treat the area with a bit of dawn dish soap.

If you already washed and dried it, may be set and too late. First use Natures Miracle to kill the urine, then rinse in cold water, then soak area,in OXI clean. Once stain is desolved, launder it.

If you have already washed it, treated it, etc. I would soak it overnight in Oxiclean. I go with hottest water the fabric can tolerate to start, and change the water and soak it again with fresh water and Oxiclean the next day. Then wash it in your washing machine. I've gotten some pretty bad stains out over the years. In the future, use an enzyme product like Nature's Miracle first, to remove the urine before laundering.

Thank you I have resolved it and was able to get the stains out with Dawn and baking soda.