Are Kylie Jenner and Jaden Smith dating? Maybe not, but the Kardashian sister called Will Smith’s son her “best friend” in a new Instagram post for the teenager’s 15th birthday. In a heartfelt post, Jenner talked about how much Smith meant to her on his big day.

“Although we can't remember exactly when we met,” Jenner wrote “I couldn't be more grateful that we did. You understand me like not many do & you always know the right time to make me laugh. And no, you haven't failed once to catch me when I attempt to walk or open the door on my every entrance. Happy birthday to my best friend.”

Jaden Smith Jaden Smith had denied dating Kylie Jenner in the past.

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In March rumors started that the two friends were dating. "They're dating," a source told Us Weekly back in the spring. "It's new, but they've been friends forever." Both Jenner and Smith denied such activity, but not that strongly. "Some people don't understand and some people do. And it's just great to have someone grow up in the same position as you and you can relate in that kind of way, so it's fun,” Jenner told E! about her friendship with Smith.

"She's one of my best friends. It's pretty awesome,” Smith also told Wonderland Magazine about Jenner. "Happy Birthday @iputthesocietyonmyback I love you Jaden!! Have the BEST day ever!! #bestkidever," Jenner’s mother Kris Jenner wrote, while sister Kendall tweeted, "happy birthday to one of the sweetest kids I know! have a good one mr!@officialjaden."

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Friend Justin Bieber also tweeted: “Everyone wish Happy Birthday to my brother for life @officialjaden!!! #HappyBirthdayJaden” Smith himself tweeted, “"It's Your Birthday" Mateo Said. I Didn't Respond. "Are You Not Excited To Be 15" He Asked. Reading My Book I Uttered "I Turned 15 Long Ago."”

Smith and Jenner spent Fourth of July together with her family, although it prompted Jenner to tweet "Media always making it seem like I'm dating everyone I'm seen with. Makes no sense to me. Don't listen to everything u see, people." We won't listen to anyone but you, Kylie Jenner!