Sue was conceived in a one-night stand at a QLD drive-in. Now, she wants to find her dad.

Sue Chapman knows exactly when and where she was conceived: August 1961 at the Mount Isa drive-in cinema in country Queensland.

She knows that her biological father had the nickname PK. She knows he was 170cm tall, with grey-green eyes and medium-brown hair.

But she doesn’t know his real name and she has never met him. She’s hoping to trigger a memory and make contact with him, after all these years.

“I’m 55 in May,” Chapman tells Mamamia. “I thought, ‘I’m going to go all out and try to find him, because if I don’t, I’ll never know.’”

Chapman’s biological mother was just 15 when she got pregnant. The teen was sent to Rockhampton to stay with an aunt, and after the baby was born, gave her up for adoption.

Chapman was brought up by “beautiful” parents.

“I had a wonderful childhood,” she says.

Through an amazing coincidence, Chapman’s adoptive mother discovered her biological mother’s family in 1989.

“Mum used to go selling party plans and she was doing a party plan at this lady’s house and they started talking about adoptions,” Chapman explains. “Mum said, ‘My daughter’s adopted – 1962, in Rockhampton.’ This lady told her mother and father. Her father is my grandfather’s brother.

“Next thing I get this phone call and this fellow says, ‘Hi, you don’t know me, but I’m your real grandfather.’ And he starts crying.”

Chapman and her biological grandfather arranged to meet up at the Caboolture races the following weekend.

‘I said, ‘How will I know you?’ and he said, ‘I’ll find you,’” she remembers.

“I get there, and the next thing, this old fellow comes walking up to me, and he says, ‘Sue,’ and he gives me a big hug, and he says, ‘Show me your hands,’ so I put my hands out. On my palm I’ve got lots of lines, more than normal. Had them all my life. He puts his hand out, and his hand’s the same, and he says, ‘Your mother’s hand is the same.’

“He said to me, ‘You can’t breed chooks from crows.’”

Chapman says her grandfather wished she’d never been given up for adoption. He was relieved to know she’d had such a great childhood.

“He said, ‘Every year on the 26^th of May I always wondered where you were, what sort of life you had.’”

Chapman’s grandfather came to her baby daughter’s christening the following year, and she also got to know other members of the family. But sadly, her biological mother chose not to meet her face-to-face. That was nearly 30 years ago. She has never changed her mind.

“I’ve always respected her wishes,” Chapman says. “I’ve known where she’s lived since 1989. I could have rocked up on her door and said, ‘Hello, here I am.’

“I said to her last time we spoke on the phone, ‘Look, are you embarrassed about me?’ and she said, ‘Yes, I am,’ and I said, ‘Don’t be embarrassed. You shouldn’t be embarrassed.’

“She’s never ever given me a real chance. It’s so sad.”

As for the identity of her biological father, Chapman has only been able to get a few small hints from her mother – the nickname PK, the conception at the drive-in.

Determined to track him down, Chapman has devoted “countless hours” to the search. She began by poring over electoral rolls, looking for someone with the initials PK. When that didn’t work, she turned to Mount Isa Facebook groups. Locals have been keen to help out, with many of them suggesting a well-known current resident with those initials.

“I got his phone number, and he was so gorgeous,” Chapman says. “He’s too young, but he said, ‘Oh look, if I knew I was, there wouldn’t be a problem! I’d welcome you with open arms!’”

She was also directed to a former resident with the initials PK.

“I rang him and had a bit of a talk. He said, ‘Oh, Jesus, I would only have been 13! My balls would have only just dropped!’

“He’s lovely. We’ve struck up a bit of a friendship and he’s been trying to help me as well.”

Other locals have suggested that maybe PK was just a nickname and not his initials.

“A lot of people have been saying back then PK chewing gum was the big thing. Maybe he chewed PK chewing gum.”

She wonders whether perhaps her biological father was a keen horserider, like her.

“Before I could walk I was on a horse. I represented Queensland with one-day eventing, show jumping. People have said to me, ‘That’s genetic, your ability.’

“That’s always made me wonder. Mount Isa, August – was he in town for the rodeo?”

Chapman, who lives in Gympie, is planning a trip to Mount Isa soon.

“I want to go out and see where the old drive-in is, or was, and have a look at where my grandparents used to live.”

She’s determined to keep searching.

“I’d really like to know about my father’s history – who he was, what he did, any medical history, what sort of a person he was.

“Time’s starting to kick on.”

Can you help? Sue Chapman can be contacted at suechapman16@bigpond.com