Gisele Bundchen is one of the most recognizable faces in the world — in part because of her career as a supermodel, and in part because of her marriage to football superstar Tom Brady. This past Saturday, she celebrated her 40th birthday and needless to say, love poured in from fans all over the world. 

But as interesting as that was — as fun as it was for the supermodel-turned-supermom — she wasn't alone in celebrating her special day. 

Gisele Bundchen has a twin sister — one that she rarely talks about, but one whom she's extremely close to.

Who is Gisele Bundchen's twin sister, Patricia Bundchen? 

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She's five minutes younger than Gisele Bundchen.

Patricia Bundchen is Gisele Bundchen's fraternal twin sister. She was born 5 minutes after her supermodel twin. They definitely look like sisters, but don't look like twins. 

She tried her hand at modeling but ultimately became Gisele Bundchen's manager. 

When the Bundchen sisters were younger, their mother enrolled them in modeling classes in Brazil. And while we all know, obviously, what happened with Gisele Bundchen, Patricia Bundchen didn't make modeling her full-time career. However, Patricia Bundchen became her twin's business manager and spokeswoman. 

She got hit on by a Dallas Cowboy.

Dallas Cowboys defensive end Greg Hardy held a truly bizarre press conference back in October 2015. Somehow, in the midst of all his controversy (specifically surrounding his arrest for domestic violence charges), he announced that he couldn't wait to face off against Tom Brady and the Patriots because he was hoping that Gisele Bundchen and her twin sister would be in the bleachers. 

But Patricia Bundchen is already married. 

Obviously, Hardy's advances towards Patricia Bundchen were rebuffed, because in 2010, she tied the knot with Rodrigo Pereira in the Bundchen's native Brazil. The whole Bundchen family was in attendance, including Tom Brady — who came with the couple's then-baby boy, Benjamin — while Gisele Bundchen served as the maid of honor at the wedding. 

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Gisele Bundchen wished her twin sister a happy birthday on Instagram.

While Patricia Bundchen doesn't have an Instagram page, Gisele Bundchen will share pictures of herself and her sister on the page from time to time. And she did the same thing on their shared birthday. "Today Pati and I get to celebrate four decades of being alive on this amazing planet! How lucky I was to be born with my twin and best friend! I am so grateful for all the people who have been a part of my journey. My husband, my family (especially my loving children!), my friends and so many others who I never got to meet but who have supported me through all these years. I’m grateful for every experience that has helped shape who I am today. My heart is so full! I am looking forward to this new chapter of my life, where I get to use the tools I’ve acquired these past 40 years in service of helping make this world a better place. Life is truly the biggest gift!" she said in a post you can see below. 

She helped manage Gisele Bundchen Intimates brand.

When Gisele Bundchen retired from the runway, she joined forces with her sister to launch Gisele Bundchen Intimates, a curated line of underwear, in 2011. Patricia Bundchen was also reportedly responsible for Gisele Bundchen's move to print campaigns and away from runway campaigns when she retired from the runway. 

She's teaching Portuguese to Gisele Bundchen's children.

The Bundchen family is extremely close, and that includes Patricia Bundchen's closeness with Gisele Bundchen's children! Patricia Bundchen told a Portuguese newspaper, in fact, that she only speaks Portuguese to Gisele Bundchen's children so that they stay tied to their roots. "I only talk in Portuguese when I’m with him. I think he must get used to the language and learn it; is important to be bilingual. He’s not just a Brady, he’s a Bundchen too," she said.

The twins come from a big family. 

In addition to Gisele and Patricia, the Bundchen family has four other girls, for a total of six girls.

She admits she's much shyer than her twin sister. 

"Unlike me, Gisele was very talkative and she wasn't afraid to be away from home for some time even when she was little," she explained. "She was very brave, and she was always trying to protect her sisters — something like 'Don't mess with my sisters or you'll have to deal with me!'"

She has nothing but good things to say about Gisele Bundchen. 

"Her willpower made her successful," she said about her supermodel sister. "She has never let the critics put her down, and this has never changed. She has the most amazing body, but what has really made her successful is her personality, her way of doing things, her professionalism."

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Bernadette Giacomazzo is an editor, writer, publicist, and photographer whose work has appeared in Teen Vogue, People, Us Weekly, The Source, XXL, HipHopDX, The Los Angeles Times, The New York Post, BET.com, and more.