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Call it a Hollywood happy ending: When The Sisterhood of the Traveling Pants was first cast, the 2005 film's four young leads – Alexis Bledel, America Ferrera, Blake Lively and Amber Tamblyn – had not all met one another, but they quickly grew close. "From the first film, we got along so well that we all try to get together whenever we're in the same city," Lively said on Good Morning America in 2008.
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TABLE FOR FOUR
True to Lively's word, the fabulous foursome gathered 'round over drinks at NYLON magazine's 2007 music issue concert in New York City.
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GROWING ... TOGETHER
All four actresses signed on to reprise their roles in the movie's 2008 sequel, The Sisterhood of the Traveling Pants 2. A memorable cliff-jumping scene was written into the script – after the group took a spontaneous leap together in real life. "It is rare, we've always said that," Bledel told GMA of the quartet's tight friendship.
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"It feels like we sort of become our characters," Tamblyn (pictured here enjoying some "late night chocolate" with Bledel on Traveling Pants 2's set) told CNN in 2008. "We just fall right into them because we are such close friends in real life, all of us."
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WORDS WITH FRIENDS
To celebrate the 2009 publication of Tamblyn's book of poetry, Bang Ditto, Bledel and Ferrera came out to New York City's Bowery Poetry Club to show their support for their sister scribe.
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Ferrera and Bledel – both activists as well as actresses – both joined the ONE campaign, traveling together to learn about the non-profit's female-focused anti-poverty efforts in Honduras.
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Lively and Tamblyn rang in 2016 together, joined by Ferrera and Bledel, of course.
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The gang reunited for 4th of July 2016. "There"s a strong chance there might be a third," Lively told PEOPLE's Jess Cagle of the possibility of filming another Sisterhood of the Traveling Pants. "The four of us are still best friends. To be able to create something together again has always been a dream of ours."
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MAKE AMERICA FERRERA AGAIN
With the 2016 election drawing near, Tamblyn (as Donald Trump) and Ferrera (as a very concerned citizen) teamed up for an episode of Lip Sync Battle. The disturbing performance was somehow a very sweet reminder of their enduring friendship.
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BABY ON THE WAY
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All of the girls turned up at the New York City premiere of Tamblyn's directorial debut, Paint It Black, in May 2017. And their support wasn't just limited to cheering on their friend when the credits rolled. “Even tonight, [Blake] explained to me how to steam this shirt over text,” Tamblyn told PEOPLE. “This shirt was all wrinkled and I was like, ‘I’m screwed! I don’t know what I’m going to do with this shirt.’ And she was like, ‘Put it in the bathroom for 20 minutes and turn the shower on. Are you good with your jewelry? What shoes are you going to wear?’ ”
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In August 2017, Ferrera posted a cute shot with Tamblyn and her daughter Marlow, simply captioned, #thefutureisSisterhood.