In utero, scans showed that his kidneys were damaged. A tiny partial blockage in the urethra, the tube that allows the bladder to be emptied, caused a chain reaction of problems as he grew in the womb.

First it damaged Max’s bladder, which then caused to his kidneys to slowly be destroyed.

Upon the birth of her son, and the diagnosis of Posterior urethral valves, Kylee Block was told Max would one day need a new kidney.

But that day came quicker than expected.

At this first appointment with Royal Children’s Hospital nephrologist Dr Cathy Quinlan at eight months of age, tests showed Max had unexpectedly tipped over from chronic kidney disease to kidney failure and admitted straight to the ward.

Dr Quinlan said dialysis kept Max alive for just over a year — replacing 15 per cent of his kidney function — until he could reach the magic 10kg mark needed for surgery.

“These children have to be big enough so that an adult kidney will fit in, that the blood vessels are big enough to be sewn together and the child has a big enough blood pressure to keep this other kidney happy,” Dr Quinlan said.

Kylee was a perfect match to donate her kidney. Max, who now has three kidneys, now likes to compare matching scars with his mum.

“I feel blessed that I was able to give him life for the second time,” she said. “It’s this special bond I have with him now.”

Dr Quinlan and the RCH nephrology team will continue to see Max once a month to check the organ, which just celebrated the important one year milestone, is still adjusting to its new home.

“We do all of this so our children have a normal life, whatever that means for that family,” she said.

“He is supposed to run and play and do whatever other children do.”

The Jan Juc boy, who turns three on Monday, has been “rebirthed” since the lifesaving operation.

“It was like he was watching from his hospital cot, taking in everything and saving up all his energy to be unleashed now,” said Kylee.

“He’s a different Max. He was so quiet and sickly and didn’t seem happy before the transplant.

“It was like a switch had been flicked. He’s on the run constantly from one thing to the next.”

To donate to The Royal Children’s Hospital Good Friday Appeal please click here or phone 9292 1166.

Words Brigid O’Connell (Herald Sun), photos Jay Town.