Gigi Hadid and Bella Hadid are welcoming a new addition to their family.

The supermodel sisters shared that their dad, Mohamed Hadid, fathered a daughter named Aydan Nix with a woman named Terri Hatfield Dull following his divorce from Yolanda Hadid in 2000.

“Over 20 years ago, our dad, while single, had a brief relationship that led to a pregnancy,” Gigi, 30, and Bella, 28, said in a statement to the Daily Mail May 29. “Aydan was born and raised in Florida, growing up with the man she lovingly knew as her father until his sudden passing when she was 19.”

After her devastating loss, the 23-year-old opted to “take a genetic test out of curiosity,” leading her to find “a biological connection” to the Hadid family, according to Gigi and Bella.

Following the discovery, the pair made contact with their younger sister in late 2023, noting that they “embraced Aydan with open arms.”

“We’ve cherished this unexpected and beautiful addition to our family,” Gigi and Bella continued. “As siblings, we’ve had many open and loving conversations—with Aydan included—about how to support and protect her.”

One way the duo intend to help Aydan, a budding fashion designer and stylist, is by preserving her privacy as much as possible. In their statement, they asked that the public “honor her wish and right to her anonymity as she continues her life as a young woman in New York.”

Keep reading to see stars you may not have known were related.

On an April 2 episode of Finding Your Roots, host Henry Louis Gates Jr., revealed that Lena Dunham had a distant ancestor in common with Larry David on her mother's side. 

Genealogist Dr. Adina Newman, known on Instagram as My Family Genie, revealed Blanchard and the Vanderpump Rules alum are allegedly related on their paternal grandmother's side dating back all the way to the 1600s.

Schroeder, a self-professed true crime fan, commented on Newman's post, "Omg I'm unwell."

The Mask of Zorro star was married to the Fifty Shades of Grey actress' mother Melanie Griffith for 20 years before they ultimately split in 2015, but that doesn't mean the stepfather and daughter's bond has been severed.

Johnson got emotional when she presented an award to Banderas at the 2019 Hollywood Film Awards.

"I come from a family of many a marriage and I got very lucky," Johnson, whose dad is actor Don Johnson, said. "I got a bonus dad who I realized that, over time, is actually one of the most influential people in my whole life," she said. "When I was six years old, my mother married a man who brought an unbelievably bright light and a whole new world of creativity and culture—and one remarkably magical little sister into our family."

The Teen Witch star and the Gossip Girl alum are half-sisters who share the same mom, talent manager Elaine Lively.

The "Ex's & Oh's" singer is the SNL vet's daughter, born from his relationship with former model London King.

The Fast & Furious star is cousins with the R&B singer thanks to her stepfather, Reverend Edward Best, who happens to be the rapper's uncle.

The late-night host and the Rescue Me creator are third cousins.

The onetime Grey's Anatomy doc has called the legendary director stepdad ever since he married her mom Kate Capshaw in 1991.

The Grown-ish star calls the rapper her second cousin. She was even the flower girl in his 2005 wedding with now ex-wife Kelis!

The actress is the daughter of the Back to the Future icon.

Not only did the Veep vet make a name for herself playing a famous daughter on the HBO comedy, but she's also a famous daughter in real life. The erstwhile Jack Bauer star is her father.

Some Emily in Paris viewers were très shocked to discover Lily is the daughter of the English Grammy winner. 

The comedian and the New York Senator are actually related, as he's the first cousin of her father.

According to a 2014 People interview, a family historian from Ancestry.com claimed that the Fannings and the Princess of Wales are all descendants of King Edward III, who ruled England from 1327 to 1377, making them very distant relatives—21st cousins, to be exact.

The actors are actually brother and sister!

Talent runs in this family, as the Reno 911! alum, Orange Is the New Black actress and This Is Us star are all cousins.

"We are blood related!" Nash wrote on Instagram January 2024, sharing a photo of the trio at the Academy Museum of Motion Pictures Third Annual Fundraising Gala. "REAL cousins!"

The SNL alum calls the Cheers icon Uncle George whenever he sees him. At least, we assume he does.

Yep, Game of Thrones' Stannis Baratheon is the real-life dad of Fear the Walking Dead's Nick Clark.

The brunette beauty and the "Stay With Me" singer are third cousins. During a radio interview, Smith admitted that the pair have never met because their family is "huge."

The Salt actor and the memorable Law & Order: SVU guest star are half-brothers.

You may not have guessed but the Bridesmaids comedian and the former View co-host are cousins.

The We're the Millers actress has the perfect mentor in the Pretty Woman star, who happens to be her auntie.

Who knew the stunning Dancing With the Stars pro is second cousins with the Friends alum?

The True Blood vampire caught the acting bug from his dear old dad who stars in both The Avengers and Thor franchises.

The Ghost Rider actor comes from an extremely talented family. One of his cousins directed The Bling Ring, the other starred in Saving Mr. Banks and his uncle directed The Godfather.

The outspoken British singer is the older sister of the Game of Thrones star. She even wrote a song about him titled "Alfie." 

The Damages star and the Lipstick Jungle actress are second cousins.

The Secret Life of Walter Mitty actress originally inspired her baby brother to get into show business.

The Parks and Recreation actress is the daughter of the legendary music producer.

The Lost actor has a very famous cousin in the Mission: Impossible star.

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