Amid the joy at Kostas Gribilas' wedding, there will be tears in memory of a Sydney, Australia man he never met.

Gribilas is alive today thanks to a heart transplant he received from 20-year-old Doujon Zammit, who died after being beat up during a vacation to Greece last year, The Daily Telegraph reports.

After recovering enough to travel from Athens to the country of his birth, Australia, Gribilas will walk down the aisle with his wife-to-be Poppy in Sydney two days after Christmas.

It's the wedding ceremony they thought they would never have.

And standing next to him during the ceremony as his best man will be none other than Doujon's father Oliver.

Friendship between an organ donor's family and a recipient is extremely rare. The two usually never meet.

But as it happened, Gribilas' details became public soon after his operation and he was among the transplant recipients the Zammit family met during a visit to Athens.

Since then, Gribilas has become firm friends with the relatives of the man who unknowingly saved his life.

"I owe the parents of Doujon not one thank you but 1,000," he said.

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