New Zealander Graham Allanson, of Feilding, has been reunited with his family - more than four decades after they were last in touch.
Mr Allanson, 58, hadn't seen his half-sister Lorraine Drabble, 53, or three half-brothers Gary, 50, Neil, 46, and Derek, 42, since he left Britain in 1967.
Despite repeated attempts to track each other down, the siblings finally got back in touch only through a chance meeting on the internet, the Star newspaper in South Yorkshire reported.
After an emotional reunion, Mr Allanson has spent the past few weeks staying with Ms Drabble at her home in Worksop and getting to know his extended family.
"It has been absolutely fantastic being here," said Mr Allanson, who works as a senior community work supervisor for the Department of Corrections in Palmerston North.
"It's just wonderful to be part of the family."
He left the village of Langold, near Worksop, in 1967, aged 16, emigrating with his mother and her new husband. They were part of a generation of Britons who took advantage of the cheap boat tickets that were sponsored by the Australian government in the 1950s and 1960s.
"We lost touch with the family - we moved from Australia to New Zealand in 1974 and completely lost touch," he said.
"I tried to find the family many times but had never been successful. They weren't able to trace me because they thought we were still in Australia and meanwhile they had moved."
Despite returning to the UK several times he was never able to track the family down - they had moved house and their phone number was not listed in the directory - but eventually he connected through a website called Genes Reunited.