Conservative Party campaign manager Jenni Byrne, right, is seen at a Harper campaign stop in Toronto, Ontario on Tuesday, August 18, 2015. THE CANADIAN PRESS/Sean Kilpatrick

Ontario Premier-designate Doug Ford has tapped a senior staffer from Stephen Harper’s government to be one of his top advisors, say sources closely linked to the Progressive Conservatives.

Jenni Byrne will be Ford’s principal secretary, according to four sources who spoke with iPolitics on condition of anonymity.

Byrne did not reply to a request for comment and neither did the party.

[READ MORE: Who is in the running for Ford’s cabinet in Ontario?]

The job of principal secretary was dragged out of obscurity by Prime Minister Justin Trudeau when he appointed his advisor Gerald Butts to the job in 2015. One source said Byrne’s principal secretary role will be “substantive,” with staff reporting to her at the premier’s office.

Of the staff appointments that iPolitics has been told about, Byrne has the most extensive experience working in government. Her year’s on the federal scene are viewed by several sources as having a steadying force on the mostly rookie government. Ford’s chief of staff Dean French is a close ally to the premier-designate but hasn’t played a prominent role in political circles since the 1990s.

During the campaign, Byrne led the party’s field operations along with Fred DeLorey. They were responsible for targeting and delivering the swing ridings that the Tories needed in order to win government.

Under Harper, Byrne quickly rose through the ranks in the Prime Minister’s Office, ending her tenure in the deputy chief of staff job. She was also his federal campaign manager in 2011 and 2015.

Since Harper’s defeat in 2015 she has worked as the vice-president of strategic communications for Bayfield Strategy.

[READ MORE: Ford’s transition team features powerful federal Conservative duo]

Of the former Harper Conservatives who joined Ford’s campaign team, Byrne appears to be the only one staying on. Sources say Kory Teneycke is returning to the private sector. The campaign’s war room manager and director of communications Melissa Lantsman is not staying on and neither is DeLorey.

Ford’s campaign director and leadership race manager, Michael Diamond, has also returned to the private sector.

Other senior positions are also filling up in the incoming premier’s office. Three sources say Mitch Davidson, who wrote much of Ford’s platform and was director of policy under former leader Patrick Brown, will hold the same position in government. A senior Tory source called the appointment a “solid choice” and described Davidson as someone who knows his files “very well.”

Andrew Kimber, who led the campaign’s war room with Lantsman, will be Ford’s director of issues management.

Multiple sources tell iPolitics that two Ford loyalists will fill the key roles of deputy chiefs of staff. Amin Massoudi has worked with the family since Ford and his late brother Rob were at Toronto city hall. Since then he has stuck close to Ford. Massoudi helped run his 2014 mayoral campaign, and was on the road with him for the Tory leadership race and the provincial election.

Ford’s other deputy chief of staff will be Simone Daniels. She is part of his transition team and played a role in logistics during the campaign. Prior to that she worked at the family’s label-making business and also worked with the Ford brothers at Toronto city hall.

Two of the sources said caucus was told about the staff appointments at the party’s first meeting on Tuesday.

The new government will be sworn in on June 29.

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