Amber Heard References 'Kate Moss and Stairs' as She Testifies About Johnny Depp and Sister's Fight

Amber Heard brought up Johnny Depp's ex Kate Moss in court last week while discussing an alleged altercation between Depp and Heard's sister, Whitney.

On Thursday in Fairfax, Virginia — where Heard, 36, is on the defense as Depp, 58, sues her for defamation — the Aquaman 2 actress said Whitney was near a staircase "in the line of fire … trying to get Johnny to stop," which reminded her of a rumored incident between Moss and Depp.

"[Whitney's] back was to the staircase, and Johnny swings at her," Heard testified. "I don't hesitate, I don't wait — I just, in my head, instantly think of Kate Moss and stairs."

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"And I swung at him," Heard continued of the alleged March 2015 incident between herself, Whitney and Depp.

"In all of my relationship to date with Johnny, I hadn't landed a blow," she said. "And I, for the first time, hit him — like, actually hit him. Square in the face."

She added, "He didn't push my sister down the stairs."

A rep for Moss, 48, did not immediately respond to PEOPLE's request for comment.

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Heard first made the Moss staircase allegation during her testimony at Depp's UK defamation trial in 2020, according to The New York Post.

"I remembered information I had heard [that] he pushed a former girlfriend — I believe it was Kate Moss — down the stairs," Heard previously testified while describing the same fight involving her sister and Depp. "I had heard this rumor from two people and it was fresh in my mind."

Moss and Depp called it quits in 1997 after four years of dating and a rumored engagement, but later appeared together briefly at the Cannes Film Festival in May 1998.

While the two were never shy about showing their affection for one another in public ("They can't keep their hands, lips, mouths, legs off of each other," a friend of Depp's told PEOPLE in 1994), their passion for one another spilled over into heated arguments.

The couple was spotted shouting at each other in public, according to reports, and one reported spat resulted in Depp's arrest. At 5:30 a.m. on Sept. 13, 1994, the actor was arrested for criminal mischief at New York's Mark Hotel for allegedly trashing his hotel room.

Police found Depp "in a state of possible intoxication" and Moss uninjured. A criminal-court judge dismissed the charge against Depp on the condition that he stay out of trouble for six months. Depp paid the Mark close to $10,000, including more than $2,000 for damages, plus the bill for the remainder of his reservation.

Moss said in a 2012 interview with Vanity Fair that she cried for "years" after their relationship ended: "There's nobody that's ever really been able to take care of me. Johnny did for a bit. I believed what he said. Like if I said, 'What do I do?', he'd tell me. And that's what I missed when I left. I really lost that gauge of somebody I could trust."

RELATED VIDEO: Amber Heard Testifies About First Time Johnny Depp Allegedly Hit Her: "It Changed My Life"

Depp is suing Heard for defamation, arguing that her 2018 op-ed for The Washington Post about surviving domestic violence tarnished his reputation and ruined his career opportunities, even though she didn't mention him by name in the article. He testified that after Heard's allegations against him, he lost "nothing short of everything."

He and Heard married in 2015 and split in May 2016, when Heard sought a domestic violence restraining order against him, accusing him of abusing her. Depp denied the claims, and the former couple settled their divorce out of court in August 2016.

Depp, who has said multiple times under oath that he has never struck Heard or any woman, has testified that his "goal is the truth" as he seeks to clear his name in the trial, which is being televised live via various outlets. When Heard took the stand Wednesday, she told the jury, "I struggle to find the words to describe how painful this is. This is horrible for me to sit here for weeks and relive everything."

Back in November 2020, Depp lost his highly publicized U.K. libel lawsuit case against British tabloid The Sun for calling him a "wife-beater." The court upheld the outlet's claims as being "substantially true" and Heard testified to back up the claims. In March 2021, the star's attempt to overturn the decision was overruled.

There will be no court this week (proceedings resume Monday, May 16, at 9 a.m. ET), and the jury involved in the Fairfax County, Virginia, case has been instructed by Judge Penney Azcarate to not research anything pertaining to the trial online while on break.

If you are experiencing domestic violence, call the National Domestic Violence Hotline at 1-800-799-7233, or go to thehotline.org. All calls are toll-free and confidential. The hotline is available 24/7 in more than 170 languages.