The actress is mom to son Valentino, 3, whom she shares with ex-husband Peter Artemiev

Julia Fox isn't pregnant -- even though she showed off a baby bump earlier this week.

The Uncut Gems star, 34, shared a video on her Instagram Stories on Tuesday, Sept. 17, wearing a white T-shirt that was cropped to show off a baby bump. In the video, Fox walked back and forth, posing from different angles as she stood in front of a mirror.

Fox wore white boxers and white bedazzled Crocs, smiling as she recorded herself. "Oops," she wrote across the clip.

A few minutes later, she shared another message on her Stories, clarifying that she isn't actually pregnant.

"Omg its [sic] for a movie! THE BELLY IS NOT REAL!!!" Fox explained.

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Related: Julia Fox Wants Son Valentino, 3, to Be a Proud Nepo Baby: 'He Needs to Own It'

Fox is already mom to son Valentino, 3, whom she shares with ex-husband Peter Artemiev.

In April, Fox revealed in an interview with Variety that she does not plan to hide her son from the public eye, but rather let him experience it firsthand.

The author and model told the outlet that she believes keeping your kids out of the spotlight as a public figure is "almost like a disservice."

"It's like I have this very highly coveted thing [and] I want to share that with my son," she explained. "We need him to be a nepo baby, and he needs to own it too."

Added Fox, "He can't be like, 'I'm not really a nepo baby,' he needs to be like, 'Yes I'm a nepo baby, and what?'"

However, as she discussed with InStyle, Fox does have a pretty down-to-earth approach to parenting, which includes being very involved in his daycare and not having a nanny.

"I don't have a nanny, so I do everything: the drop-off, the pickup, the lunches, the feeding, the shower, the bath, all of it, the doctor's appointments, the play dates," she told the outlet.

She continued, "Obviously, I'm lucky that my family is here in New York, all the grandparents, the aunts, the uncles. So if I have to go do something, it's very easy for me to call upon somebody."

"And they're all very eager to take care of him because he's just the sweetest, most fun little ray of light," she added of the toddler.