Talk about seeing double. We may think we know these famous faces, but their siblings have such a striking resemblance to them that they could almost pass as twins.
Some of these stars are just as well-known as each other, like Chris and Liam Hemsworth and Paris and Nicky Hilton. But other stars' brothers and sisters lead a much quieter life out of the spotlight.
Let's see which celebrities have lookalike siblings…
WATCH: Holly Willoughby shares rare video of lookalike sister
Holly Willoughby and sister Kelly
The This Morning star occasionally shares photos of her sister Kelly and every time she does, fans are quick to comment on their stunning genes. Apart from the different in their hair colour, the sisters could be twins!
The Duchess of Cambridge and sister Pippa
From their dark hair to their slender noses and rosy cheeks, Kate and her younger sister Pippa are almost carbon copies of each other.
Michelle Keegan and brother Andrew
Who knew Michelle had a handsome younger brother? The actress celebrated National Sibling Day in 2018 by posting a photo with Andrew (left) and writing: "I know this was yesterday but happy #nationalsiblingday @rookeegs I always try and make you look good… and you're welcome! #rideordie4life."
Rochelle Humes and sister Lili
Talk about carbon copy. Rochelle is the spitting image of her half-sister Lili (centre), who she reconnected with, thanks to Love Island's Kem Cetinay. Rochelle said on Happy Mum Happy Baby podcast: "Two years ago, I was at our management's Christmas party and Love Island's Kem was there. He was chatting away and said, 'I got to talk to you... as soon as I became a celeb, I promised my friend Lili that I would talk to you as she's your sister on your dad's side.' I knew of her and met up with her when I was five, but it was so complicated as they were a lot younger and my dad wasn't involved.
"On a drunken night out, Kem asked me if he could give her my number. She WhatsApped me and I didn't reply till the morning. We planned to go out for dinner with my other sister and brother and I made Marvin come with me because I was so scared."
Rochelle added: "We are literally the same people, Marvin was like, 'OMG, there's more of you.' We've spoken every day since. It's like we've known each other all our lives."
Dermot O'Leary and sister Nicky
Dermot 'Leary stunned back in 2020 when he shared some previously unseen photos of his big sister, Nicky – and you can certainly see the family resemblance. The TV host shared a sweet dedication to his sibling on Instagram in celebration of her birthday, including one retro snapshot taken when they were both children. Another showed her in her graduation robe, after completing her PhD. "Late night big love to my big sister," Dermot captioned his post. "Happy Birthday Nicky. Incredible human, and the best female role model a young brother could hope for. X."
Paris Hilton and sister Nicky
From their blonde manes to their fabulous style, Paris and Nicky Hilton are like two peas in a pod.
Angelina Jolie and brother James
The actress' brother James Haven is basically the male version of Angelina.
Andrea McLean and sister
Fans were quick to comment on the likeness between the Loose Women panellist and her sister after she posted this photo on St Patrick's Day in 2018. "When your sister manages a surprise trip over from Ireland on St Patrick's Day... #family#mumanddaughterday #love," Andrea wrote on Instagram.
Penelope Cruz and sister Monica
The Spanish siblings are both accomplished actresses in their own right, but did you know that Monica acted as her sister's body double in Pirates of the Caribbean, when Penelope was pregnant with her first child?
Chris Hemsworth and brother Liam
What did we do to deserve two Hemsworth brothers in the spotlight?
Emma Watson and brother Alex
She's the more famous of the Watson siblings, but Emma's younger brother Alex actually starred with the Harry Potter actress in Burberry's Spring/Summer campaign in 2010.
Paul Mescal and sister Nell
Paul Mescal isn't the only creative talent in his family. The actor also has a lookalike sister, Nell, who is making her own waves in the world of music. The talented 19-year-old is a singer-songwriter and has released some of her songs on Spotify and Apple Music. Paul is a huge fan, and despite having a beautiful singing voice himself, he admitted Nell "is better" than him.
AJ Pritchard and brother Curtis
Former Strictly Come Dancing star AJ is literally identical to his brother Curtis, who is only one year younger. The 27-year-old is loved by fans after his role on the BBC dance contest but his brother Curtis has also made a name for himself after appearing on 2019's Love Island. After leaving Strictly, the pair also had a small stint on Hollyoaks.
Billie Piper and sister Elle
The actress, who is the eldest of four children, most resembles her younger sister Elle. From their pouty lips to their fierce eyes, the pair could be twins! Billie sent her fans into meltdown back in 2017 when she shared a photo of her lookalike sibling on Instagram, praising Elle's fashion line.
"Sisters can be a pain in the hole but my god they're impressive… check out this little hustler @pippy.piper @pipers.clothing. If you like to feel casual and FIT@ this is your brand. And if you like dressing your sons in leggings – there's a kids line to follow," she wrote.
Dakota Fanning and sister Elle
Dakota's younger sister Elle has become a Hollywood star in her own right after featuring in Steven Speilberg's Super 8. The actress has also had leading roles in Maleficent, Ginger & Rosa and We Bought a Zoo.
Vanessa Hudgens and sister Stella
The former High School Musical star is very close to her younger sister Stella, and regularly takes her to Hollywood events and premieres.
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