For years, Gigi and Bella Hadid were an inseparable sister duo. Now, a DNA test has changed everything.

For years, Gigi and Bella Hadid have walked red carpets side by side, inseparable, stunning, and undeniably close.

Fashion's golden sisters, raised in the spotlight and admired around the world, their bond seemed unshakeable and complete.

But what the world, and even Gigi and Bella, didn't know was that somewhere else, far from the flash of cameras and catwalks, there was another sister, named Aydan Nix.

Now, they have revealed her to the world.

In a statement shared with the Daily Mail, the supermodel siblings confirmed that Aydan is the daughter of their father, Mohamed Hadid, and a woman named Terri Hatfield Dull.

According to the sisters, Aydan was born following a "brief romance" between Mohamed and Dull, which took place after his divorce from Gigi and Bella's mother Yolanda Hadid in 2001.

"Over 20 years ago, our dad, while single, had a brief relationship that led to a pregnancy," the sisters told the publication.

Aydan, who was born and raised in Florida, grew up believing another man was her biological father, until his sudden passing when she was 19 years old.

Watch: Gigi Hadid's Vogue controversy. Post continues after video.

"After his passing, she decided to take a genetic test out of curiosity, and that's how she discovered a biological connection to us," the statement continued.

The sisters first connected in 2023.

"From that moment on, we've embraced Aydan with open arms. She's spent time with all of us, including our dad, and we've cherished this unexpected and beautiful addition to our family."

The statement went on to add that Gigi, 30, and Bella, 28, have had "many open and loving conversations" with Aydan about "how to support and protect her".

"Aydan and her family value their privacy, and we fully respect that. We kindly ask others to do the same and honor her wish and right to her anonymity as she continues her life as a young woman in New York."

Gigi, Bella, and Aydan share the same dad, Mohamed Hadid. Image: Getty

According to the Daily Mail, Mohamed Hadid's relationship with Dull ended before she became aware of the pregnancy.

A source close to the family described his relationship with Aydan as "cordial and pleasant," adding, "There's mutual respect... But there's also discretion."

The publication also noted that Mohamed had been expected to attend Aydan's graduation from the Parsons School of Design earlier in May but reportedly cancelled about a week prior.

Aydan, who recently completed her studies, aspires to build a career in fashion as a designer, stylist, and influencer.

According to her public LinkedIn profile, she majored in Fine and Studio Arts and partook in a summer study abroad program at Parsons Paris.

Aydan recently graduated and aspires to build a career in fashion as a designer, stylist, and influencer. Image: Instagram/@toospoiled

"My work blends editorial styling, branding, and cultural storytelling through a multidisciplinary lens, shaped by hands-on experience in fashion, costume design, and visual media," reads her bio.

Aydan has assisted stylists on high-profile red carpet events and editorial shoots, and has worked closely with designer pulls, fashion closets, and set styling.

"I've also independently directed and styled photo campaigns, developed artist books in collaboration with emerging creatives, and conceptualized fashion-forward PR events," she wrote.

The 23-year-old also said that, growing up, she was "obsessed" with her mother's Vogue magazine collection, "flipping through every issue and imagining myself behind the scenes of those stories".

"That early obsession turned into a career path rooted in curiosity, culture, and the drive to create."

Feature Image: Getty/@toospoiled.