Dominik's tiny, hairy hands disappear in the manly, silky-smooth grasp of his girlfriend as she reaches across the table in a tender gesture affirming their gender-bending love.
Before they started dating two years ago, Dominik Sejda, 45, and Andrea Kajzarova, 32, both underwent sex changes, one of just a handful of similar couples in the Czech Republic.
But a boy named Radim, whom Dominik gave birth to 25 years ago, makes their family even more special -- he is now becoming a woman named Viktoria.
"I think there has only been one case of a (transsexual) parent and child on record" worldwide, says Czech sexologist Petr Weiss.
"We don't know why transsexuality occurs. But we maintain there are certainly inherent dispositions, though we don't know whether they are genetic," he told AFP.
Dominik and Andrea, who both hail from the north-eastern Czech Republic and work as ambulance assistants in Prague hospitals, met on a transgender website at a time when Andrea was in the neutral phase of gender change.
"She had a man's genitals when we met, but she had a neutral name and looked rather like a woman," Dominik, formerly Ilona Tomeckova, told AFP as he sipped a beer in a Prague pub.
Dominik, who left his family 20 years ago, learnt he could become a man only after the 1989 demise of communism in the former Czechoslovakia.
"During communism, it was taboo. Everyone told me I was either a hermaphrodite or a lunatic who will end up in an asylum," he said.
"Then my doctor told me my kid can't have two fathers, so I found my ex-husband a lover, left everything behind, spent two years crying for my son and moved to Prague to start the switch. I got hormones within a year," he added.
The openness he found in the Czech capital was like a breath of fresh air after life in the provincial eastern city of Ostrava.
"People in Prague are more tolerant, they are used to transvestites and various shows. The city is full of lesbians and gays," said Andrea, who earned her master's degree in economics as a man named Tomas Kajzar.
A former bodybuilder, now studying to become a registered nurse, Andrea started her gender switch six years ago.
"I got the hormones when I was 26, but my problem was that I never believed I could become a genuine woman, because I was too masculine," says Andrea, who is completely feminine except for her large hands.
"My family never learnt to live with it. They are religious and take this as a sin," she says with a trace of regret in her voice.
Dominik has no regrets over the costly and painful switch.
"Why? It was a relief. I have no regrets at all, not even about having a child, because I know I won't be able to have children now," he said.
After meeting Andrea, Dominik decided to resume contact with the family he had left behind, only to find out his son was turning into a girl.
"She looks like a woman, she has the hips and all," Dominik says about Radim as he becomes Viktoria.
"But she doesn't yet have a clear idea about her role or sexuality -- if she's after boys or girls. She thinks she's lesbian but I don't know," Dominik adds.
Interviewed by public broadcaster Czech Television last year, Radim believes his need to switch gender is a matter of genetics.
"I found a sexologist in May, she sent me to different checks, including genetics. My diagnosis was always 'transsexual'," he said.
Sexologist Hana Fifkova agrees that transsexuality is most likely genetic.
A January article on Britain's New Scientist website said many studies on identifying transsexual people are focusing on brain matter, but worldwide research is so far inconclusive. Doctors are keen to find concrete physical evidence potentially "to make a case for delaying puberty to improve the success of a sex change later," it said.
Dominik, meanwhile, believes his "cultivated and effeminate" father would have changed his gender had it been possible under communism.
His grandchild may bring yet more clues.
"I have learnt I have a granddaughter, or maybe a (future) grandson. Simply, my daughter -- as a boy -- fathered a baby with a woman," said Dominik.
"They took her to kindergarten and when the girl was offered a skirt, she said she wanted trousers instead. This is exactly what I did 40 years ago!"
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