The mystery surrounding the real identity of Khloe Kardashian's biological father can be solved with a simple DNA test, and RadarOnline.com has learned there's a $250,000 offer on the table.

Sirius XM Satellite personality Gregg 'Opie' Hughes of The Opie & Anthony Show announced on Tuesday morning that he would ante up a quarter of a million dollars if Khloe, 27, would take a DNA test to prove that the late Robert Kardashian is her father.

If Khloe accepts, the $250,000 will be donated to a charity of her choice.

Khloe Kardashian has spent years wondering if she is really a Kardashian and even made it part of her TV show, by taking a DNA test. But RadarOnline.com has learned there was one major flaw — she only tested the maternity with her mother Kris Jenner, and did no paternity test to prove that Robert Kardashian is her father.

In April 2009, an episode of Keeping Up With The Kardashians aired in which Khloe wanted to prove once and for all she was not adopted, so she took a DNA test.

But interestingly, she compared her DNA only to her mother’s, not Robert’s or her siblings — which could have proven conclusively that Robert was not her biological father.

Robbie Powell is reportedly the “real father” of Mariah Yeater’s baby — although she’s claiming Justin Bieber is the dad — and RadarOnline.com has exclusively learned that Robbie was arrested in San Diego over the Thanksgiving weekend.

According to the arrest report, Robbie was busted on November 26 at 11:41 p.m. for drug and burglary charges. The 23-year-old was charged with four felonies and one misdemeanor — possession of a controlled substance (methamphetamines), possession of drug paraphernalia, and three charges of commercial burglary.

Robbie is not eligible for release and currently remains in the San Diego Central Jail where he has a combined bail amount of $7,000. He has two court dates set for later this week.

A judge has decided the man being detained in connection with the disappearance of Robyn Gardner in Aruba must remain in jail for at least sixteen more days and ordered that he submit to a DNA test.

Gary Giordano, 50, is being held while authorities investigate the circumstances under which Gardner disappeared. He claims the 35-year-old drowned when they went snorkeling on August 2, but Aruban authorities have said they doubt the veracity of his story.

His lawyer Michael Lopez argued he should be released from custody.  "The Department of Justice at this time does not have any basis to request prolongation of his detention," he said, while insisting his client is innocent of any crime.

DNA tests (unlike politicians) don’t lie.

Arnold Schwarzenegger’s now-infamous housekeeper Mildred "Patty" Baena proved her boss was the father of her son by arranging a secret DNA test, RadarOnline.com has learned exclusively in a joint investigation with Star magazine.

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A Los Angeles judge said Billie Jean was not Michael Jackson’s lover – and now he is facing the potential consequences.

READ THE COURT DOCUMENTS HERE

A woman who says she’s Billie Jean Jackson is suing Judge Mitchell Beckloff for discrimination, emotional distress and prejudice, in a $600 million lawsuit filed in LA Superior Court on Tuesday, RadarOnline.com has learned.

READ THE COURT DOCUMENTS HERE

Judge Beckloff had previously thrown out Billie Jean’s claims that she was married to the pop star and is son Blanket’s birth mother.

But in the new lawsuit, Billie Jean, who is representing herself, claimed Judge Beckloff failed to provide her the chance to prove paternity through a DNA test.

PHOTOS: Michael  Jackson - A Life In Pictures

She also alleged Jackson’s ex-wife Lisa Marie Presley has been stalking her.

“Michael Jackson's family is adverse and will not allow mother and son to meet,” she wrote.

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“The loss has harmed the Plaintiff emotionally and physically and has kept her from her son and their home while other families remain free from stalkers and are afforded protection of the Courts, her stalker, Lisa Marie Presley prevails."

Judge Beckloff is the presiding judge over Jackson's multi-million estate.

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