Bobbi Kristina Brown's court-appointed conservator filed an amended lawsuit Friday that claimed boyfriend Nick Gordon gave her a "toxic cocktail" and then put the only daughter of Whitney Houston and Bobby Brown face down in a tub of water. The wrongful death suit gives a harrowing account of the famous daughter suffering at the hands of her boyfriend apparently based on security-camera footage.

According to papers filed in the civil action, Gordon arrived at the couple's Rosewell, Georgia, townhouse Jan. 31 at 6 a.m. after "being out all-night on a cocaine and drinking binge." The suit said that the couple then "became embroiled in a loud argument," which ended in the master bedroom, reported People.  

The papers claim that Gordon then gave his girlfriend a "toxic cocktail" that caused her to become unconscious, left her in the bathtub and then came out wearing a different outfit. There was another female at the home at the time, and after coming out of the bedroom, Gordon laid his head on the woman's ankle and said, "Now I want a pretty little white girl like you," alleged the lawsuit, which mentions that some of Brown's teeth had been knocked out.

It was not until 15 minutes later that another guest went to check on Brown and found her unresponsive and with "another tooth hanging loosely from her mouth," the papers claim.

"Defendant then began to slap her saying, 'wake up,' and also started performing CPR between slaps," according to the papers.

Bobbi Kristina family Bobbi Kristina Brown and Nick Gordon smile with family at the premiere of 'Sparkle' at Grauman's Chinese Theatre on Aug. 16, 2012, in Hollywood, California. Photo: Getty

Nearly six months after she was found unconscious, Brown died July 26 in hospice while surrounded by family. She was 22. Gordon has denied any involvement in her death. 

The lawsuit was originally filed  on June 24 in Fulton County Superior Court by Brown's court-appointed conservator Bedalia Hargrove; she also filed the amended complaint that adds wrongful death to the list of claims made against Gordon. He was accused in the original suit of assault, battery, intentional infliction of emotional distress and transferring money from Brown's account into his own without authorization.

"I have filed today an amended complaint against Nicholas Gordon adding a count for wrongful death and for pain and suffering," Hargrove said in a statement to People. "We will leave no stone unturned in seeking justice for Bobbi Kristina Brown."