Boyzone star Keith Duffy will spend the day in bed with a tub of ice-cream.
"Just chilling with the family is always the best," he said.
"Lying in bed next to the wife, with the kids beside us, watching a movie, eating Ben and Jerry's ice-cream and popcorn sounds incredible.
"If I could spend all day doing that, I'd be happy.
"We work so hard, so turning into couch potatoes for the day sounds perfect."
Keith is dad to son Jay (18) and Mia (13) and says being a father is the best job in the world.
"Being a dad is the most important thing to me," he said. "I was a very young dad; I was 20."
"Jay is now 18 and my little girl Mia is a very special little girl – she has autism and we've had a lot of obstacles to overcome. She's doing great and she has given me a bigger belief in myself."
Radio host Ray D'arcy will be celebrating his son Tom's first birthday.
"Tom is a year today, and Kate is a six-year-old girl and, like every six-year-old, is obsessed with herself.
"So I don't think Father's Day is on either of their radars.
"But hopefully she'll make me a card and I may even get a bowl of porridge in bed and a flower from the garden."
Brian Ormond and wife Pippa O'Connor welcomed their bouncing baby boy Ollie into the world nine weeks ago.
But between the late-night feeds and nappy changes, Brian says the Big Day almost passed him by.
"I totally forgot about it until Pippa told me," laughed Brian.
"But I'm sure we'll have a relaxed family day – nothing too big."
Brian – who is also dad to Chloe (12) – says Ollie is quite a character: "He's flying; I can't believe how fast time has gone, but he's great."
Former Westlife star and presenter of RTE's The Hit Nicky Byrne says since his father died four years ago he has a new-found appreciation for the day.
"I was very blessed to have a great relationship with my dad. I only have good memories.
"He gave me two pieces of advice. No matter what you do, always tell the truth, because people can help out.
"The other thing is never bring the police to the door."
Nicky has twin boys Jay and Rocco and is expecting his third child later this year.
While there's plenty of R&R for those Irish dads, its non-stop training for rugby star Brian O'Driscoll.
The dad of one is Down-Under in the middle of the Lions Tour.
While he won't get to spend the day with wife Amy Huberman and baby Sadie, the 34-year-old star will be counting down the days until his two ladies touch down in Oz to visit him.