Khloe Kardashian 'Will Do Everything She Can' for Brother Rob to Win Primary Custody of Daughter Dream

Khloé Kardashian is behind brother Rob Kardashian 100 percent as the Keeping Up With the Kardashians sibling reportedly seeks primary custody of 3-year-old daughter Dream, whom he shares with ex Blac Chyna, a source close to the family told PEOPLE Thursday. Kardashian's special bond with her brother and niece extends even to this difficult legal situation, the insider explained.

"Khloé has always been very close with Dream," they said. "When Rob had custody of her as a baby, Khloé often helped out. She really loves Dream."

"Khloé will do everything she can to help Rob get custody," the source added. "She thinks this is best for Dream."

News broke Tuesday that Rob was seeking primary custody of his daughter with Chyna as TMZ revealed the shocking content of a sealed court filing, in which Rob reportedly accused Chyna of hosting parties at her home constantly while Dream is there. He also alleged Chyna "snorts cocaine," is always drinking and spends $600 on alcohol every day. Kardashian even reportedly made a comment in the filing, saying her niece has been "decidedly more aggressive" as of late and says she doesn't want to go home to mom Chyna.

In addition, Rob reportedly accused Chyna of being violent, with her behavior rubbing off on Dream, who is allegedly using language not suitable of a toddler and being violent with other children.

In the filing, Rob asks that Chyna be allowed to parent her daughter on the weekends with supervision present, which would be a major shift from the joint custody agreement they came to in September 2017 after a contentious split.

The formerly engaged couple, at the time, alleged abuse on both sides, with Chyna claiming Rob had published nude photos of her on social media without her consent, violating California's revenge porn laws.

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