The Liberal leader announced Hadrian's birth to his 330,000-plus followers on Twitter, with a discreet close-up photo of the baby's tiny hand clutching his finger.
Since then, he's been home with his wife, Sophie Gregoire, and kids Xavier and Ella-Grace, privately enjoying the new addition to their family. No tweets. No Facebook posts. No photos. No public appearances.
But while Trudeau seems intent on shielding his infant son from the glare of the public spotlight, the Liberal party has had no qualms about using Hadrian's birth to help build up its data base of potential supporters and donors.
Newly elected party president Anna Gainey, a Trudeau confidant, sent out an email blast last week urging well-wishers to send the party their names and email addresses, along with congratulatory messages that would be passed on to Trudeau and Gregoire.
“Don’t expect to see much of Justin in the news for the next few days, right now he’s where he should be — with his family,” Gainey said.
“I imagine many of you would appreciate a chance to welcome baby Hadrian and express your excitement and happiness for the family, so we wanted to give you the opportunity here.”
The dissonance between Trudeau's circumspect conduct and his party's willingness to exploit the birth of his son underscores the balancing act facing a political leader with young children.
"It's kind of a double-edged sword," says Karen Brunger, president of the Toronto-based International Image Institute.
On the one hand, voters love to see politicians with their cute kids, the younger the better. And being seen with kids is generally a plus for the politician, making him or her seem warmer, more human, more caring, she says.
"I don't know a politician who doesn't use their children," Brunger says, noting that municipal, provincial and federal politicians often send Christmas cards or campaign brochures plastered with photos of themselves posing with their happy families.
But there's a fine line between featuring one's children occasionally and being perceived to be exploiting them for political gain. And figuring out precisely where that line is can be "challenging," says Brunger.
"It's such a fine line. Can you think of another line of work where family plays such a role?"
From her perspective, Trudeau's handling of his son's birth was "sweet" and not exploitative. The party's handling of the occasion was "much more obvious" and, therefore, more likely to prompt eye-rolling.
Not since Brian Mulroney have Canadians had a political leader with an infant child. Mulroney's youngest son, Nicolas, was born the year after Mulroney became prime minister in 1984.
Before that it was Pierre Trudeau, whose three sons — including his eldest, Justin — started life living at 24 Sussex Dr., the prime minister's official residence.
The current occupant of 24 Sussex, Stephen Harper, has two teenaged children, Ben and Rachel, who were 10 and seven respectively when he took office.
Cynical members of the parliamentary press gallery used to refer to Nicolas Mulroney, who was often carried by his mother or father at official events, as "the prop." Hadrian's eventual public debut will no doubt elicit a similar response in some quarters.
But Liberal MP Dominic LeBlanc contends that kind of cynicism is an unfair knock on politicians with young kids.
"It's not fair because if you're doing those jobs as Mr. Trudeau did, as Mr. Mulroney did, as Justin is doing ... here's the problem. You have so little time to do things with your family that every time you do it becomes, because of your job, a public event or a source of public interest," says LeBlanc, a childhood friend.
For instance, he says, if Trudeau takes the kids to a ball game, it winds up becoming a public event, with fans lining up for autographs or posing for pictures with the leader. Even on vacation out of the country, LeBlanc says Trudeau is constantly approached by Canadian tourists.
Having grown up in a "fish bowl" himself, Trudeau's capacity to mix private and public life is probably more than most people would feel comfortable with. But LeBlanc says Xavier and Ella-Grace, at six and five, are already emulating their father, readily joining him to pose for photos taken by total strangers.
Being a political leader also inevitably means summers and many holidays are spent travelling the country. A leader with young children will often take his kids along just to spend time with them.
"Somebody who's trying to do a job that's often seven days a week, if they can integrate their family into their work routines, it makes a much healthier political leader," argues LeBlanc.
"Justin will be a much happier and positive political leader if he gets the right balance between seeing his family and spending time with them and being able to include them, where appropriate, in his work obligations."
Trudeau's own father used to take his three boys on official visits to foreign countries. And LeBlanc, who himself grew up with a single politician dad — Romeo LeBlanc, who served as the elder Trudeau's fisheries minister and eventually went on to become governor general — also recalls joining his late father as youngster on work trips.
Far from being exploitative, LeBlanc says the experience was positive.
"Some of the nicest memories I have of my father was when he was minister of fisheries visiting the outports of Newfoundland or the northern coast of British Columbia and I got to go with him during summer holidays or on a school break," he says.
"And I assume Justin would have had 10 times those occasions with his father and if history is allowing him to have that experience with his kids, it's terrific."
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