MONTREAL - Justin Trudeau, the Liberals' star candidate in the Montreal riding of Papineau, got some sound campaign advice on Tuesday from someone with a bit of know-how on the subject -- his mom.

Trudeau hit the streets of the ethnically diverse, working-class neighbourhood with his mother Margaret as he tries to follow in the footsteps of his charismatic father and win a seat in Parliament.

Margaret Trudeau, the vivacious former wife of Pierre Elliott Trudeau, calls election campaigns exciting, although she said her last foray into the political world in the mid-1970s was more than enough.

"I hoped not (to endure another campaign), but you have to let your children follow their dreams," she told The Canadian Press between knocking on doors with her son.

"Justin's dream has always been to be in politics. He loves politics, he breathes politics."

Margaret Trudeau, who now lives in Montreal to be closer to her sons and her growing troop of grandchildren, is now an outspoken mental health advocate since going public with her own battles with bipolar disorder in 2006.

The Trudeau family matriarch had some advice for her eldest son and aspiring MP: talk from the heart.

"I think people want him to talk from his heart," she said.

"They want to know what concerns him and what his vision is and what he thinks he can do for people.

"People want authenticity and I know Justin is a very authentic person and he'll be a very good candidate and he'll work hard."

Mother and son mingled with older voters in a park and briefly knocked on a few doors together handing out pamphlets before Margaret Trudeau continued rapping on doors with other members of her son's team.

Justin Trudeau, 36, is in a tough battle with incumbent Bloc Quebecois MP Vivian Barbot in a longtime Liberal riding that went to the sovereigntist party in the 2006 federal election.

Trudeau said his mom got involved in his political future by helping to sell memberships when he was seeking the Liberal nomination in Papineau. Her advice has been well received.

"It's a family effort and I'm glad to have her along," he said.

"Her advice is mostly around staying real and staying true to myself and my values and not getting swept up in everything that goes with politics."

The rookie politician is also facing attacks in cyberspace in the form of a spoof of his welcome video on his own web page and from a fringe separatist group intent on ensuring that anyone but Trudeau wins the riding.

The Young Patriots of Quebec is promising to protest Trudeau's official campaign kickoff Wednesday at his riding headquarters as part of its "No Trudeau in Papineau" campaign.