WillShawn Mendes and Camila Cabello's latest single, currently sitting at number two on the Billboard charts, not only become a "Song of the Summer" contender but the track to finally replace Lil Nas X's "Old Town Road" from it's number one perch? The sultry video, in which the two play lovers who ultimately can't keep their hands off each other or their clothes on, certainly has helped the single's promotion, and the chart question remain intriguing. However, that video has also fueled rumors that Mendes and Cabello are more than just collaborators. Recent pictures of the pair holding hands out in public has only served to fuel that fire.

Though, this didn't all start with the latest single, "Señorita,". These two have known each other for much longer than just a few weeks. Here, a timeline of their friendship.

2014

Mendes and Cabello go all the way back to 2014, when they opened for Austin Mahone. This was pre-solo career for Cabello, though. She showed up to the tour with the rest of Fifth Harmony, but it was Cabello who really wanted to get to know Mendes. In their V magazine joint digital cover, the two shared their first impressions of one another. " I remember I wanted to hang out with you, but you were always on the tour bus, just learning guitar," Cabello told Mendes, to which he replied, "Yeah, that was me. I didn’t talk to anybody. You were the only person that talked to me. Like, you were the only one of everybody on that tour who would say words to me. Actually, I think if we go into our DM’s or something, there’s a photo from the day we met, I think." The rest of the story goes that while they were on tour, Mendes was intrigued by Cabello's high spirits. Instead of staying on vocal rest or practicing choreography, she was out there doing cartwheels outside of the tour bus.

2015

Well, apparently even though Mendes thought Cabello was "crazy" for her tour antics, a friendship was born. By the time spring 2015 rolled around, Mendes was promoting his album, Handwritten, and doing a lot of radio press. On Capital FM, Mendes played "Lips, Wife, Leave It" (basically a wholesome version of f--k, marry, kill), and when asked if he would marry Cabello, Jade Thirlwall from Little Mix or Chloë Grace Moretz, guess who he chose. "Because I know Camila well, I'd probably wife Camila," the crooner said.

Six months later, the two released a duet called "I Know What You Did Last Summer." According to Cabello's Rolling Stone interview in 2015, they came up with the song when they ran into each other backstage at Taylor Swift's 1989 tour, where Mendes was the opener and Cabello came on as a special guest (this was well before her Reputation tour opener days). "We were just backstage hanging out, I pulled out my guitar and we were just messing around, not really thinking about writing a song," Mendes said. But the funny thing about this backstage encounter, though, is that Cabello said that was "the first time we had ever really spent more than a few minutes talking to each other," even though six months prior, Mendes said he would "wife" Cabello because he knows her well. What constitutes knowing someone "well" these days?

So, anyway, two attractive young adults released a song and naturally the dating rumors ensued. Mendes attempted to put the rumor mill to rest in October 2015 by telling People that they were "just really close friends" and that they never dated. Around the time that their first duet was released (we're looking at November 2015), the two appeared on The Late Late Show with James Corden to do a little song promo, and to also address some of those dating rumors. James Corden had the gall to straight up ask if they had ever made out, but Cabello nipped that one pretty quick. Mendes said that every time he would "try to make a move" Cabello "just, like, swerves me off," to which she replied, "He friendzones me, he calls me kid."

2017

Then, everyone kind of forgot about those dating rumors, until Cabello released "Crying in the Club" in May 2017 and Mendes tweeted "You're incredible" in response to the music video for the single, and the tweens who shipped these two in the first place hopped right back on that bandwagon and pushed the dating rumors forward again. By December, Mendes did refer to Cabello as "girlfriend material" in an interview with The New Paper, but again hammered home the point that they were "best friends."

2018

Best friends would braid each other's hair back stage, and best friends would also openly profess how much they value their friendship, like Mendes did when he told Zane Lowe that Cabello is his "favorite person in the whole world" in April 2018. At the time, Cabello was in a relationship with dating coach Matthew Hussey, and Mendes had been spotted with Hailey Bieber (then Baldwin). Eventually Mendes would lay to rest any rumors that they were dating just before the 2018 Met Gala.

2019

Fast forward to the 2019 Grammy Awards in February, where Cabello and Mendes performed separately on stage. Backstage, however, they had time for hugs.

After a few supportive tweets (coming from both performers) for a few months after the Grammys, they were spotted sharing a meal at a restaurant in Los Angeles. Roughly one month later, they released their second duet, "Señorita," and shared a video to go along with it. And to fuel those dating rumors even more, a few days after the release of the video, Cabello and her boyfriend reportedly broke up.

During a Q&A, one fan bravely asked Mendes if he would go out with her, but not until after she asked if he and Cabello were dating first. He shook his head, which is typically read as a sign for "no" but he did not verbally confirm or deny the rumors about the relationship. (He's denied it plenty enough in the past, though.)

That brings us up to date, when paparazzi saw Cabello and Mendes holding hands in West Hollywood and hugging on a street corner. Just in time for the duet promotion cycle to begin.

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