A dad was running for charity when he got life-changing news about his son

His sick son, Max, 5, finally had a kidney donor.

Born with renal dysplasia, the Wodonga boy had been having dialysis treatments his whole life while awaiting an organ transplant.

Twice before, there had been hurdles, with either the donor falling through or Max being unwell.

This time would be third time lucky; Harley felt it in his bones as his feet pounded the back roads to Melbourne.

Two days into a five-day run to The Royal Children's Hospital to raise money and awareness for Border charity Country Hope, his partner Emma shared the news that their son's medical team had found a kidney match for Max.

"It was awesome!" he said.

"I felt like we were running towards Melbourne for a kidney."

Having started MAXimum Miles for Country Hope in Wodonga the day before on September 3, which was also his 36^th birthday, Harley only felt more motivated to complete the campaign.

He arrived at the Children's Hospital on Father's Day, as planned, raising $24,000 for the charity that had supported his family with financial and emotional support since Max's birth.

As part of the Australian and New Zealand Paired Kidney Exchange program, Harley donated his own kidney to another recipient across the ditch last week.

He said they didn't tell many people because the exchange had fallen through twice before last year.

"It only felt real once Max was getting pushed into the hospital rooms," Harley said.

"Now he's recovering in hospital, but he should be coming home pretty soon and it's going to change his whole life."

With Max's health needs taking a turn for the worse a year ago, Harley, Emma and their four other children had to move to Melbourne, leaving behind their jobs, family and friends on the Border.

Max needed dialysis treatments four times a week at RCH, as well as ongoing medical tests and hospital stays.

Every Monday, Tuesday, Thursday and Friday mornings, he spent hours hooked up to a dialysis machine that cleaned his blood and balanced his fluids, helping him stay healthy enough to keep growing as he awaited a kidney transplant.

"Max did his last dialysis the day before his transplant," Harley said.

"He's turning six in February and we've enrolled him in school next year; he'll be starting out in Melbourne to see how he goes.

"He's so excited to start school!"

Set up in 2019, the Australian and New Zealand Paired Kidney Exchange program combined the established projects in each country to benefit living donation schemes in both nations.

Eight people were involved in the exchange involving Harley and Max to change four people's lives.

Harley said he felt beyond relieved everything had gone without a hitch.

"I can't believe it," he said.

"It's unreal.

"Max was so excited to get his operation; he was so brave!"

Country Hope's regional co-ordinator Kristy McMahon shared Max's development recently at the charity's major fundraiser On Key 4 Kids gala in Albury, which raised $210,000 overall.

"We're thrilled Max has his new kidney and finally gets the chance to live the life of a five-year-old boy, instead of spending half of his life in hospital," she said.

"What Max and his whole family have endured is unimaginable, but it's why Country Hope exists; to get members of our own community through these very rough times."