Khloe Kardashian is "protective" of her niece Dream Kardashian.
The 35-year-old reality star - who has 22-month-old daughter True with her ex-boyfriend Tristan Thompson - has formed a strong bond with her three-year-old niece, whose father is Khloe's brother Rob Kardashian, and mother is his former fiancée Blac Chyna.
Khloe reportedly "stepped up" to be a support system for both Rob and Dream following Rob's 2017 split from Chyna, as sources say she "always wants" to help babysit the tot.
An insider said: "After Rob and Chyna split [in February 2017], Khloe stepped up even more to help out. Khloe is very understanding and loves Dream a lot. She always felt protective of Dream.
"Khloe was always very motherly. After Dream was born, Khloe was the best aunt. She always wanted to help out."
The 'Keeping Up with the Kardashians' star hasn't stopped doting on Dream since welcoming her own daughter either, as she now sets up play dates for the two youngsters.
The source added to People magazine: "This hasn't changed since True was born. Dream is often at Khloe's house. Now it's even better because True and Dream can play together."
Meanwhile, Rob, 32, recently filed documents in Los Angeles asking to be the main carer of his daughter, and Khloe is keen to support him in his custody battle.
Another insider reported: "Khloe has always been very close with Dream. When Rob had custody of her as a baby, Khloe often helped out. She really loves Dream.
"Khloe will do everything she can to help Rob get custody. She thinks this is best for Dream."
In his documents, Rob asked a judge to limit the time Chyna spends with their daughter to just weekends with a nanny present as he believes she's a danger and isn't behaving appropriately around their little girl.
The reclusive star accused his former lover - who also has seven-year-old son King Cairo with her ex-partner Tyga - of regularly hosting parties at her home in front of Dream and invites strangers round to get drunk with her.
Rob believes Dream's behaviour has changed recently as she's started "naked twerking, and acting out sexual positions that she said her mom taught her", as well as swearing and using language he insisted he never uses around her.
However, a lawyer acting for Chyna has blasted Rob for moving to take the tot away from her "hands-on, extremely loving" parent.
Lawyer Lynne Ciani said: "So Rob Kardashian - who has ... posted illegal revenge porn against Chyna - wants to take custody of Chyna's beautiful daughter, Dream, away from her hands-on, extremely loving mother?.
"And Khloe Kardashian ... wants to take her niece Dream away from her loving mother, Chyna? Oh, please.
"Chyna will vigorously contest this latest despicable attempt to take away her daughter in a court of law, where she will keep prevailing against her ex-fiancé Rob and the other malicious and vindictive members of his family."