"He says he will give me a million dollars every time if I laugh at his jokes," said the nine-year-old from Allambie Heights Public School on Sydney's northern beaches.

Archie admits his father is only trying to make him happy but the jokes, well, "they're not funny," whispered Archie.

For his dad Tim, 46, who grew up without a father, "every day is Father's Day".

"Being a father is everything: It's my greatest source of fun, really, and enjoyment. They do rub me up the wrong way sometimes, but it's good fun," Mr Hamilton said.

Mr Hamilton is the eighth of nine children, all born within 11 years, raised in Sydney's Epping by an "inspiring" single mother after their dad left.

On Father's Day when Mr Hamilton was a child, his five brothers and three sisters would celebrate his mother. "We always used to look after mum on Father's Day as well. She raised nine kids by herself, and she was mother and father and everything else to us."

Without a father to use as a role model, the father of two has looked to teachers, his big brother (who fathered him when he was growing up) and coaches.

"It's a bit of a jigsaw puzzle," he said. "And you put it together, and sometimes you put the wrong piece in the wrong place. But when you do put the pieces together, you get a sense of satisfaction." Mr Hamilton works overnight shifts caring for disabled adults because it leaves him free to spend most afternoons with Archie and his brother, Zachary, 6.

He also coaches his sons' cricket and soccer teams.

Mr Hamilton is happy to see many other fathers take on the role of primary carer, doing more of the day-to-day caring for children.

"It's great that fathers are having more of a role raising children in this day and age, and sharing the load more," said Mr Hamilton, whose wife works in public relations.

High school teacher Matt Cavallaro's sons, Rylee, 4, and Jaxen, 2, are at an age when their conversation is full of poo jokes. Even the word poo is hilarious.

In between, the two boys say they love that their dad plays "the tickle monster with them" and is funny.

Like Tim Hamilton, Mr Cavallaro, of Warriewood, says one of the big advantages of his job is the time he has with his children after school and on school holidays.

"I've made a few career decisions where I have chosen time with my family over money," he said.

Since his wife returned to work full time as a marketing manager, she is the bigger bread winner, something he says is becoming more common.

"I value time, and time with my family, as opposed to getting paid a bit more."

Rylee, 4, has bought a new screwdriver for his dad, although Mr Cavallaro admits he is not very handy.

Meanwhile Archie Hamilton has bought his dad a head massager. His brother Zachary, 6, has bought Mr Hamilton an alarm clock, hopefully one that won't go off too early on Sunday morning.

When Archie is asked if his dad is like other dads, he replied: "Different."

How is he different?

"He is MY dad," Archie said.