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Kate Winslet and Leonardo DiCaprio met in 1996 while filming the blockbuster Titanic, playing one of the most iconic couples in cinematic history: Rose Dewitt Bukater and Jack Dawson, star-crossed lovers who met on the ill-fated Titanic in 1912. The two weren't friends before filming, but they knew of each other – enough for Kate to have her eye on Leo. In a 1998 interview, she admitted: "My god, did I want to Leo to play that part."
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At first, however, Kate confessed she was a little wary that she'd be distracted by Leo's good looks. "I did think to myself beforehand, it's going to be hard, because you know, what if I really fancy him?" she said in a 1998 interview. "And I so thought I was going to, because he is absolutely gorgeous." Luckily for her, that was a hurdle they never had to overcome: The two instantly clicked, Winslet said, and were friends from the beginning.
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Filming the movie was a huge, seven-month-long undertaking that involved hours in a water tank (for Kate, without a wetsuit, which led to a case of pneumonia). The young actors bonded throughout filming, though, so much so that Kate's friends got a little jealous. "The closeness and the strength of the friendship that we had is something a lot of my friends envy like mad," she said. "But to me he's just silly old Leo."
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After Titanic hit theaters – to massive success – the two hit the red carpet together at the 1998 Golden Globes, both up for trophies in the best actor/actress categories. Despite questions about a romantic connection from interviewers, the stars insisted they were "just good buddies," as Leo said.
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Ten years after Titanic's release, Kate and Leo were as close as ever: At the 2007 Oscars, where they were both nominated, we saw a glimpse of their bond when the camera panned across the audience – and caught Leo winking at Kate.
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Two years later, they reunited on screen in Revolutionary Road, a decidedly less romantic story about a couple whose marriage is disintegrating in the 1950s. The film, directed by Kate's then-husband Sam Mendes, was a project years in the making. "We were actively looking for something to do together," Leo said. "It felt really natural. She's my homie."
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And throughout the press tour, they couldn't stop singing each other's praises. "She's a consummate professional," Leo said of his costar during a a visit to the Today show. "She's the best." To which she replied, "He's the best, too!"
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Of course, Leo and Kate in another movie together was a recipe for awards show success. The two hit the red carpet at the Golden Globes in 2009, where they dished on their friendship. "It's a great to work with one of your best friends," Leo said. And of course, as Kate said: "With the attention that the film has gotten, we've been getting to spend more time together, which is a great bonus." (It was a pretty great bonus for us too, Kate!)
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That same night, when Kate took home the award for best actress in a drama for the film, she gave Leo the ultimate teary-eyed shout-out in her acceptance speech. "Leo, I'm so happy I can stand here and tell you how much I love you, and how much I've loved you for 13 years," she said (as he blew her a kiss from the audience). "I love you with all my heart, I really do."
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The pals cozied up at the 2012 Golden Globes, where Kate took home a prize for her turn in Mildred Pierce (Leo was nominated for the titular role in J. Edgar). But it was later that year, in December, when we were truly reminded of the depth of their friendship: At Kate's wedding to Ned Rocknroll, Leo reportedly walked her down the aisle.
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This awards season has brought us even more Leo and Kate, as both have been nominated at every major show (him for The Revenant and her for Steve Jobs). However, Kate seems to care more about Leo's success than she does her own. "I've been so focused Leo and him winning everything," she said. "He is my closest friend in the world and I just couldn't imagine not being there to support him."
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The feeling is mutual: When asked about Kate at the BAFTA Awards (where both took home prizes), Leo laughed and said, "Kate – that's my homegirl!"
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At the 2016 Oscars, the two had yet another adorable red carpet reunion. And later, when Leo finally won his Best Actor Oscar, it was Kate who gave him a huge hug – and teared up during his heartfelt acceptance speech.
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Over a year after Leo's long-awaited Oscar win, Kate dished about her text conversations with her friend in a new interview about her film, The Mountain Between Us, which required the cast to film scenes in freezing temperatures. Obviously, this gave Kate some serious Titanic flashbacks, so she decided to text her BFF. "[Leo and I] did speak before filming and he did sort of say to me, 'Oh my god, you are crazy. It's going to be freezing cold. Do you honestly know what you are sending yourself up for?' " she told E! News. "I would send him little photos of me saying, 'Thinking of you,' as I am lying in the freezing snow-covered ice and he would just send back slightly worried emojis." And while Kate says there are currently no plans of an onscreen reunion, the actress remains hopeful for the future. "There's nothing that Leo and I have planned. But as always I would love to work with him again one day but who knows? It might not happen until we're 70." Please, guys, do it for us?
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In July 2017, DiCaprio hosted a charity auction in the South of France, and Winslet was there to support him. To raise money for environmental causes, the pair auctioned off the opportunity for a fan to have dinner with the actors. And at the event, they also reunited with fellow Titanic star Billy Zane, who plays Winslet's onscreen fiancé Cal — before she meets DiCaprio's Jack, of course. The trio documented the moment with a group photo.
Winslet and DiCaprio were also spotted hanging out outside of the event, at his villa in St. Tropez, where they relaxed together poolside.
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In August 2017, Winslet revealed that she and DiCaprio are just as Titanic-obsessed as the rest of us: They still occasionally quote lines from the film to each other, and they find it absolutely hilarious: “Sometimes we do quote the odd Titanic line back and forth to each other, because only we can,” she said. “We find it really funny.” We do too, guys!
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Of course, there's some friendly competition between the two stars, too. Winslet couldn't help but compare her intense new film, The Mountain Between Us — which is about two people (Winslet and Idris Elba) fighting for their lives after their plane crashes and leaves them stranded in the High Uintas Wilderness in Utah — to DiCaprio's The Revenant. Her film was shot in the Canadian Rockies, and conditions were even worse, Winslet says, than what DiCaprio went through while filming The Revenant, the movie he famously slept in an animal carcass to prepare for. “We weren’t ready for how hard those environments were to actually work in,” Winslet said of the experience. “I’ve heard Leo say similar things about The Revenant. We had quite a lot of crew who were from that film, and they did go so far as to say that ‘this is tougher,’ which we were quite proud of.”
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Out and about at the Toronto International Film Festival, Winslet couldn't stop talking Titanic to Entertainment Weekly, PEOPLE and InStyle on the carpet. She said that the memories of filming the 1997 movie were still clear in her mind, but that what she cherishes the most from the experience was bonding with the cast and crew — Leo in particular. "For me that’s one of the best things about being in this business is getting to work with incredible technicians who are always great, committed, professional, fun people to spend time with and to go to work with, and we really had that on Titanic," she shared. "And, of course, I walked away with one of the greatest friendships of my life in my back pocket, which is Leo.”