Actor Will Arnett, who grew up in Toronto, wasn’t that funny as a kid. Not according to his father, James “Jim” Arnett. “Looking back, he was quite serious. But by the time he was a teenager he was funny and amused his family. He was always a quick wit.”

Whether or not it’s hereditary, Jim’s hedging his bets. “I wouldn’t say I’m funny. I have no idea what others would say. Wait . . . my wife says that I have a wicked sense of humour.”

What she meant, Will says in an email, is that his dad’s humour “is derived mainly from witchcraft.”

Will Arnett is best known for his role on Arrested Development as George Oscar Bluth (G.O.B.), which earned him an Emmy nomination, but he has also starred in the films Semi-Pro, Blades of Glory and Hot Rod. He is drawing on personal experience to play Chris Brinkley in the NBC show Up All Night, as one half of a couple trying to juggle two jobs and a newborn.

“In Up All Night, he’s almost playing himself,” says Jim. “It’s a terrific show and all the young people I know in Toronto say the show really speaks to their life.”

Will married Amy Poehler, a Saturday Night Live alum and star of the comedy Parks and Recreation, in 2003. They have two boys, Archie, 3, and Abel James, 20 months, and live in New York. But back in 2001, Jim and his wife, Alix, didn’t even know Will was seriously dating Poehler until Alix visited her parents in Winnipeg and saw a picture of Will and a blond in a place of honour among the family photos. That’s when she knew it was serious.

“My wife said, ‘Who is that? I’ve never seen this picture.’ And [Alix’s] mother said, ‘Will sent it to us. It’s his girlfriend.’ To be honest, we had never heard of her.” After they were introduced, they went to New York. “She took us to Saturday Night Live and we met Lorne Michaels,” he says. “The key thing is that we really liked her and we liked them together.”

The Arnetts will reunite in Toronto on April 12 at a benefit for the Toronto East General Hospital, where Jim served on the board for seven years, including two as chairman. Will shares the stage with comedian Jerry Seinfeld, with proceeds going to the hospital’s $200-million redevelopment project. “I’m thrilled that Will is doing this,” Jim says. “He’s an extremely busy guy and to take the time to do this, I’m really honoured.”

The father and son couldn’t have taken more divergent paths. Jim graduated from Harvard University (he took a class taught by Henry Kissinger), became a corporate lawyer, and was president and CEO of Molson Breweries from 1997 to 2000. Will has admitted to being a troublemaker, who at age 12 was sent to Lakefield College School, north of Peterborough, Ont. He graduated from Leaside High School, but dropped out of Concordia University to head to New York, where he took acting lessons. “I became an actor primarily out of boredom with my family,” Will cracks.

But Jim says Will was a good kid, despite hearing about many escapades after the fact. “I’ve learned more about when he did get in trouble from reading what he’s said in interviews. And that’s the thing. You can’t punish your child 20 years later.”

So what is it like to be a comedian’s parent? For one thing, Jim and Alix can never be sure who is on the phone: Will often impersonates someone else when he calls. And when Will took them to Jimmy Kimmel Live! last year, naturally he made a punchline out of them. “Will says something like, ‘Oh, yeah. I was afraid to leave the kids at home and my aging parents at home in case they set the house on fire.’ ”

When it comes to parenting, Jim’s advice is to be cautious but encouraging to budding creative types. “If your child really wants to be an actor, don’t make them be a banker. Go over with them what the risks are. But you have to give them your full support. Don’t fight it. Support it.” As for Will, he says children need to know who’s in charge. In his case, “that’s my wife, then the nanny, then the dog, the neighbour across the street who’s got a glass eye and the dude I’m guessing is our gardener.”