Kidney failure is a nasty process. When the kidneys lose their ability to regulate the amounts of salt and water in the body and filter waste products out, excess water and waste can accumulate in the body. Eventually this can lead to a life-threatening build up of fluids and waste products in the blood as well as altering the blood chemistry and affecting the functions of the heart and the brain. It's a long and painful process that you wouldn't wish on anyone, yet it's exactly what Clare Burton was facing in 2007, not for herself, but for her five year old daughter Angel.
Angel was born with kidney problems that caused her health to rapidly deteriorate. Her urine was leaking into her kidneys and a scan showed that they were badly damaged. In October 2007 an operation was scheduled to create an artificial valve in a last chance scenario to save the child, and it was during this operation that the girl shocked the medical world. Surgeons were astounded to find that Angel suffered from a condition known as duplex kidney, where a second set of healthy kidneys had grown right next to the damaged ones. Despite the rarity of the condition Angel had another surprise waiting for the doctors, as she'd also grown extra ureters (which allow urine to be taken to the bladder) meaning her second kidneys could easily take over the workload of the damaged ones. The second set of kidneys had already started picking up the slack from her damaged kidneys and, once the damaged set were removed, they took over completely.
Angel is now eight years old and has made a complete recovery. Doctors still don't know why the extra organs didn't show up during the regular scans the child had over the first five years of her life, but they assume it's because the new organs are so close to the old ones.