Throughout his twenties, thirties and forties, every night was party night for Rick Mettel, a musician who went on to own a series of clubs in New York City. By the time his first child arrived, when Rick was 49, the American was content to swap a hectic social life for fatherhood.
He had met Jackie Spillane, a Dubliner who manages farmers' markets, when he was 40 and she was just 21. The couple eventually settled down together in the Wicklow village of Rathnew.
Although he is now 63, Rick has no regrets about becoming a father later in life. He combines his work as an artist with looking after his 15-year-old daughter and 12-year-old son. He cooks for them while his wife is at work, home-schools his daughter, and travels with her every year to a different European city, often taking in a rock concert together.
"I'm 63, but people think I'm a lot younger because I look and act younger," he says. "Having children has really kept me young at heart.
"A lot of people become parents in their 20s, but when I look back at my 20s, I see that I was really stupid. The more experience you have, the better you are as a parent."
The sexagenarian is part of the growing cohort of men in Ireland in the throes of fatherhood at an age that was once associated with retirement, slippers and enjoying grandchildren.
Just as the age of new mothers is creeping up, the age of men facing into nappy changes and sleepless nights is advancing, figures suggest.
The Central Statistics Office doesn't routinely collect data on the age of first-time fathers, but figures it released in 2013 indicated some 3,000 of the more than 72,000 births recorded for the previous year were to fathers aged 45 and older.
Fertility treatments have helped women to conceive at an ever increasing age, but doing so naturally becomes difficult for most as they enter their 40s. Few limits apply to men, who can father children for as long as they are capable of having sex.
The 56-year-old actor Alec Baldwin, for instance, is due to become a father again later this year. The star's wife, 30-year-old yoga instructor Hilaria, announced the news on New Year's Day by posting a photo on Instagram of the couple on a beach, with their toddler Carmen touching her mother's growing baby bump.
The actor also has a 19-year-old daughter, Ireland, from his former marriage to Kim Basinger. But he says he's a better father these days.
Men who come to fatherhood in middle age often have more time and money to devote to their children than men in their 20s and 30s who are busy working their way up the career ladder, according to Laura Haugh from online parenting forum MummyPages.ie.
"Studies have shown that older dads tend to be calmer, more patient, have a less frantic lifestyle and are less career-driven than their ambitious, younger counterparts," she says. "These dads tend to have more time to nurture their children and be more involved in every aspect of their lives.
But Baldwin is a spring chicken compared to other celebrity fathers. In December, Stevie Wonder became a dad for the ninth time at the age of 64 with girlfriend Tomeeka Robyn Bracy. The singer, who has been married twice and has children with five different women, reportedly told friends he wasn't always available for his kids when he was younger.
In Ireland, PJ Mara, whose role as Charlie Haughey's spin doctor was recently portrayed by Tom Vaughan-Lawlor in the RTE drama Charlie, welcomed his baby daughter to the world in 2013, when he was 71.
He didn't reveal the identity of the baby's mother.
The former press secretary also has a son in his thirties from his 40-year marriage to Breda Brogan, who died after a long illness in 2003. After his latest offspring was born, Mara suggested he was not heavily involved in his children's upbringing. "On a day-to-day basis, I am not the most hands-on father in the history of the world," he said. "It hasn't made a whole lot of difference in my day-to-day life. I'm very busy; I travel a lot. Her mum has to do all the [things]."
The advancing years of these high-profile fathers has revived a debate about the ethics of conceiving a child at an older age.
After all, Mara will be 92 when his daughter turns 21 and the average life expectancy for Irish men is 76.8 years.
Children of older fathers may have to become their carers at a relatively younger age. There is also a greater risk of these men not being around long enough to see their children become adults or parents themselves.
Rick Parfitt, a singer and guitarist with Status Quo, voiced similar concerns in 2013. The rocker became a father to twin boys in 2008, when he was 59. "It upsets me to think that I won't see them fully grow up," he said.
There are other perils of delaying fatherhood, with a growing body of research showing older fathers pass on just as many medical conditions to their offspring as women who don't become mothers until their 40s. A study in the journal Nature found rates of autism and schizophrenia double every 16.5 years of a father's age.
While women are born with a complete set of eggs, men continue to make new sperm throughout their life, creating more potential for genetic mutations.
"It is not only a woman's fertility that is affected by age," Laura Haugh says. "So don't delay if you choose an older man as your life partner."