Joe is six years her senior -- you do the math.
This is one relationship that's been in the works for quite a while.
While answering fan questions on Periscope on Monday night, Gigi Hadid opened up about the very beginnings of her relationship with Joe Jonas. Though the two just went public as a couple this year, they've apparently been friendly since meeting at the GRAMMYs in (by our estimate) 2010.
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"We met at the Grammys when I was 13 years old," Hadid revealed. "And he asked me to a baseball game, and I said, 'No.'"
According to photographic evidence, Hadid's stepfather, music producer David Foster, brought Hadid and her mom, Real Housewives' Yolanda Foster, to the 2010 GRAMMY ceremony when Hadid would have actually been 14 years old. Jonas -- six years her senior -- was also present at the ceremony with his brothers, Nick and Kevin Jonas, when the trio were still making music as the Jonas Brothers. See their red carpet flashback photos below!
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It's certainly possible that Hadid is simply misremembering her age at the time the pair met (Hadid was not photographed at the 2009 ceremony, when she would have still been 13, although the JoBros were nominated for Best New Artist that year), but she isn't fuzzy on the day's details.
"I was so nervous; I literally didn’t even know what it meant to hang out with a boy," she elaborated. "And also, GRAMMYs are on a Sunday, and I didn’t want to tell him that I had school the next day, so I was like, 'No, maybe next time.' "
Enter Yolanda Foster. Jonas, then 19 or 20 years old, depending on the actual year, "wrote his number on a piece of paper and gave it to my mom," Hadid said.
"And then we've been friends ever since," she concluded. "Except now. We're more than friends. Obvs."
Now 20 and 26, respectively, Hadid and Jonas are quickly becoming one of our favorite couples to watch! ET caught up with Jonas at the iHeartRadio Music Fest in Las Vegas over the weekend, and he spilled on his new music and double dating with Hadid's sister, Bella, and her boyfriend, The Weeknd. See the interview below.