Why is Janet Jackson in the middle of the Jackson family drama?

A family source tells FOX411 that the Jackon family's mind-blowing row comes down to one motivator: access to the late Michael Jackson’s estate.

“Michael’s siblings want money and from day one, [their mom] Katherine wouldn’t side with the siblings on their mission,” a closely connected Jackson family insider told FOX411’s Pop Tarts column.

So why then is Janet Jackson, herself worth $100-$150 million, right in the middle of things? Unlike her brothers, who haven’t had much musical success since their childhood days in the Jackson 5, Janet is rolling in it, plus, her boyfriend of a couple years is billionaire businessman Wissam Al Mana.

“Janet’s involvement is purely about her devotion to anything Randy does and says, and is a product of that old saying ‘idle hands are the Devil’s workshop,’” the source explained. “She only has money going out, and nothing new coming in, so she doesn't want to be in a position where her family is counting on her like they did Michael. Thus, she would like to see her family gain control of Michael's money.”

Not only did Janet sign the letter accusing the executors of Jackson's estate of fraud, she was one of the key players involved in tearing through the gates of the Calabasas compound this week and reportedly partaking in aggressive action to remove electronics and communications tools belonging to Prince, Paris and Blanket, in an effort to prohibit their tweeting and relaying information with the outside world.

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    Probably the most shocking part is that Janet was allegedly caught on tape slapping her niece Paris and calling her a “spoiled little bitch,” to which the 14-year-old retorted with a slap of her own and screamed at her famous aunt: "This is our house. Not the Jackson family house. Get the f**k out!"

    Prince took to Twitter on Thursday to publish a direct message he sent to family members demanding he speak to his grandmother, along with Janet's reply: “Don’t let them please.” The tweet was later deleted, apparently on request from Katherine who had asked him to "cool down."

    We’re told that MJ’s kids are still reeling over their grandmother’s bizarre “disappearance,” and feel that she was “brainwashed and taken away.” Those close to them are concerned about the emotional impact the ordeal has had and how it will affect their ability to trust those around them. The saga also has Prince, Paris and Blanket grieving the devastating loss of their dad all over again.

    However, Katherine’s homecoming on Thursday did bring about some much-needed relief.

    “grandma’s here! #thankyougod <33,” Paris tweeted, while her older brother Prince Michael wrote: “As long as I can remember my dad had repeatedly warned me of certain people and their ways. Although I am happy my grandma was returned, after speaking with her I realized how misguided and how badly she was lied to. I’m really angry and hurt.”

    This tweet has also been removed.

    "This is all going to end badly. Now, TJ is trying to do damage control but the damage is so deep, things are to far gone," said our source. "TJ knows that Randy, Jermaine, Rebbie and Janet are still threats so he wants to keep custody permanently because they would pose no threat to him and Michael's children anymore. TJ will discourage contact until things have settled down a bit."

    Reps for Katherine, Janet and the Jackson brothers did not respond to a request for comment.

    The turmoil began when some of the siblings signed a legal letter accusing the executors of Michael’s estate – John Branca and John McClain – of fraud, forgery, exploitation and abuse of MJ’s finances. Next up, their mother Katherine, the former guardian of Michael’s three children was last weekend officially reported to be “missing” by other relatives. She was soon located in Arizona, although for almost two weeks she was not in contact with the young children who were supposed to be under her care. Jermaine Jackson tweeted that his mother was on a medically ordered vacation after news of his “missing” status surfaced, however her mysterious absence ignited a physical altercation which required police intervention on Monday. Subsequently the matriarch of the household lost custody of Prince, Paris and Blanket, who are now under the temporary guardianship of their cousin, Tito’s son TJ Jackson. Attorneys for Katherine have confirmed she will file for a reinstatement.

    Editor's Note: This article references a report by TMZ.com that Janet and Paris Jackson were involved in a physical altercation. TMZ.com later retracted this report.