Darcars Automotive Group, the family-owned Silver Spring-based auto sales giant that operates 31 franchises, reorganized its top ranks last week with the naming of the founder’s son John Darvish, 41, as president and chief executive and the creation of a chief operating officer post for his brother, Jamie Darvish, 38.

The realignment, which had been in the works for a while, is “just succession planning,” John Darvish said.

The changes, already in effect, do not include a new role for their high-profile sister, Tammy Darvish, 50, who has often been the face of the company, starring in commercials and representing Darcars at philanthropic events such as a recent veterans’ hiring event at the Verizon Center.

She also was the first woman chairman for the Washington Area New Auto Dealers Association.

“She will remain a vice president,” John said of his sister, adding that the changes are his father’s wishes. “Her role is exactly the same.”

In a statement, Tammy Darvish said, “I look forward to and am hopeful for the continued success of my family’s business. I am unaware of the details of any firm decisions made with respect to management of the company.”

The brothers take over a sprawling company founded in 1977 by their father, chairman and founder John R. Darvish, 77, who suffers from Parkinson’s disease, according to his son.

“My father is going to remain as chairman, and that will give him the opportunity to stay involved,” said John Darvish, who has been with the company since 1993, working everywhere from the parts department to his most recent position as vice president and general manager. “This was not a sudden decision.”

With 1,800 employees in 21 dealerships across Maryland and Virginia, Darcars is one of the nation’s largest car dealers, in terms of revenue.

The company, which includes a dealership in Jacksonville, Fla., sells 50,000 vehicles annually and generates $1.25 billion in revenue. It also operates one of the largest Toyota dealerships in the nation, among its many brands.

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