NEW YORK (CNNMoney.com) -- Carolyn Kepcher, the blonde co-star of Donald Trump's 'The Apprentice,' has been fired.

The 36-year old sidekick, who in addition to her role on the show ran the Trump National Golf Club in posh Westchester County north of New York City, was fired earlier this week.

Rhona Graff of the Trump Organization confirmed to CNNMoney.com that Kepcher no longer works at the company.

Trump's daughter Ivanka has replaced Kepcher in the role, while Trump's son Don Jr. is the successor to the 78-year old real estate lawyer George Ross on the show.

The show's Web site states Ivanka and Don Jr. will "fill in for" Kepcher and Ross "during multiple episodes of 'The Apprentice'" in the fifth season.

Ross is still "very much a part of the company," Graff said, but because the show's next season is being taped in Los Angeles instead of New York, his appearances on it will be limited.

Graff said Trump wishes Kepcher well but had no other comment on the matter.

An article citing unnamed sources in Thursday's New York Post, which first reported the story, indicated Kepcher's lack of focus as a reason for the firing.

Trump had had trouble reaching her recently as she had been away on a trip to give a speech, the sources told the newspaper.

Kepcher had hired agents at ICM to handle book and TV offers, and Westport Entertainment to manage her speaking engagements and product endorsements, the newspaper reported.

"The Apprentice" has been in decline for a while and it's possible Kepcher's departure is a business move as much as anything else said Jennifer Armstrong, a staff writer for Entertainment Weekly, who has covered the show. She noted that the show's production is moving to Los Angeles next season, too.

"In some ways maybe it's good to shake things up a little bit," Armstrong said.

But it's a risk, too, according to Armstrong who says Kepcher was "a really key component to the show."

"She was there from the beginning," said Armstrong. "The three judges had the same kind of magical chemistry. She was great at being a henchman to Donald but she brought a female element to table, too."

Entertainment Weekly is owned by Time Warner, CNNMoney.com's parent company.

Marketing Evaluations, which conducts surveys of the public's familiarity with and opinion of various celebrities, found that while 80 percent of general U.S. population knows who Trump is, only about 25 percent know Kepcher and Ross.

And among those who know those three personalities, the view of Trump is far more negative than the view of Kepcher and Ross.

"That [Trump's high negatives] is not necessarily a bad thing. It's just the way he enlists an emotional response," Henry Schafer, vice president for Marketing Evaluation, which uses the survey to compile "Q Scores" used by networks and advertisers to judge personalities' appeal, told CNNMoney.com. "He's someone people love to hate."

A source knowledgeable in the matter told the Post that Trump advised Kepcher to "take some time off and spend it with her family, and then get another job."

Kepcher is married and has a son, Connor, 6, and a daughter Cassidy, 4.