Katie Bergin had been trying to track down her father Anthony Brown since her mother gave her pictures of them together when she was a baby.
She "found her needle in a haystack" 11,000 miles away in Australia after a plea for help on Facebook.
"Dad said it's like the moon and stars coming back to earth," said Ms Bergin.
The pair had both been trying to track each other down - but Ms Bergin's break came with a little help from one of the genealogist firms featured on the BBC programme Heir Hunters.
"It has been such an emotional time, it's been a whirlwind and I have never been more happy," said Ms Bergin, 51.
"The first time we spoke on the phone, we both just cried and cried. After 10 minutes I had to say 'I'll call you back' because I was so emotional.
"I bought a ticket to Australia ASAP and got here as soon as I could. I just wanted to hug him!"
Mr Brown, now 77, left Wrexham as a 17-year-old to join the armed forces.
He met Ms Bergin's mother Anne in 1964 as he worked at the Scarsdale Arms pub in Kensington, London.
Katie was born in 1965 after a brief relationship but Mr Brown only saw his daughter once, when he gave her a panda teddy bear.
"I've always wanted to track down Dad ever since Mum told me the story," Ms Bergin said.
"She gave me a few pictures of Dad, told me his name was Anthony Brown and was originally from Wrexham.
"I've spent my life searching phone books, calling random A Browns or latterly searching for A Browns on the internet but as you can imagine, A Brown is quite a popular name."
Ms Bergin, who grew up in London finally had a breakthrough in April.
A partner from one of the probate research firms which features on the BBC's Heir Hunters show saw her post on Facebook and offered to help.
"After a few weeks of work, he said he is probably overseas," Ms Bergin added.
"That was a huge blow as I thought my needle in a haystack search in the UK had just got much, much bigger! But somehow, he found a number for dad's sister-in-law, who lives in Shropshire.
"I called her and sent some photos and she said that's your dad - but he's in Australia! She gave me his number and I called. It was an amazing moment when I first heard his voice!"
Mr Brown emigrated to Australia in 1975 and became a car salesman. Now retired, he lives in Albury, New South Wales with his wife Marge.
"He had told Marge he had a long-lost daughter and his dream was to meet me," said Ms Bergin.
"He has suffered a heart attack and cancer but said he couldn't go until he met me.
"I took the panda he gave me as a kid with me to Australia and I'll be spending my 52nd birthday with him in June - my first with my dad."
A former RAF serviceman, originally from Wrexham, has been reunited with his daughter 51 years since their only meeting - when she was nine months old.