Rob Kardashian has claimed Blac Chyna is conducting a "smear campaign" against him, after she filed to request a mental health evaluation for him in their ongoing custody battle.
This week, the 'Keeping Up with the Kardashians' star had his emergency request to strip his ex-fiancée Chyna of custody of their three-year-old daughter Dream denied by courts, after a judge ruled the case doesn't need to be dealt with immediately.
Following the decision, 31-year-old Chyna filed to delay a court hearing scheduled for next month, in order to have a child custody evaluation to examine her ex's mental health, which would involve approving a mental health professional to perform the test on the Arthur George sock designer and their daughter.
But Rob, 32, has now fired back with new legal documents claiming Chyna - whom he has accused of a danger to Dream as she was allegedly drinking and partying in front of her - is trying to discredit his fight for custody by alleging he is mentally unstable.
In court documents viewed by Us Weekly magazine, Rob claims to have witnesses who can attest to Chyna's alleged substance abuse, and insists he does not "drink alcohol to excess" and does not "use cocaine or opioids or any illegal substance".
Rob also alleges Chyna rejected his offer to pay for a private judge to handle the custody case.
The documents state: "While a public evidentiary hearing is not ideal for any of us, Petitioner has declined the offer to take this matter to a private judge. I have no other recourse than to proceed toward evidentiary hearing as I want to protect Dream."
Although courts this week ruled to deny the emergency filing Rob submitted in January, he can still go ahead with his custody battle, just not under emergency circumstances.
In the court papers filed by Rob at the beginning of the year, he asked that Chyna's time with Dream be limited to just weekends and with a nanny present.
He claimed Chyna - who also has seven-year-old son King Cairo with ex-partner Tyga - regularly hosts parties at her home in front of Dream and invites strangers round to get drunk with her.
Rob also said Dream's behaviour had changed recently as she has started "naked twerking, and acting out sexual positions that she said her mom taught her."