Addison Rae Wishes 'Queen' Kourtney Kardashian a Happy Birthday: 'Most Caring, Loving' Person

Addison Rae is celebrating her friend Kourtney Kardashian on her special day.

As Kardashian turned 43 on Monday, the 21-year-old Tik Tok star honored the occasion with loving tributes on her Instagram Story. Beginning with a solo shot of the Poosh mogul, Rae wrote: "It's @kourtneykardash day 🖤."

Rae then posted a photo of the pair donning matching outfits and said: "Happy Birthday beautiful Aries queen 🦋."

Concluding her tribute, the Addison Rae Goes Home star shared a pic of herself planting a kiss on Kardashian's cheek. "Truly, one of the most caring, loving, kind, and fun people I know ♈❤️," added Rae.

The two He's All That costars met because Kardashian's eldest son, Mason, is a big fan of Rae. From there, Kardashian and Rae were able to develop a close friendship — despite their 22-year age gap.

Addison Rae/Instagram

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Rae has said she considers Kardashian to be a "mentor" to her.

"Kourtney has been an amazing mentor for me and she's been such an amazing friend and person to really just ask anything to," she told Entertainment Tonight last August. "She's been very honest and helpful. I mean, this is something that she's lived through for half of her life and it's something that she can definitely speak on it and give me her honest feedback on. So she's been an amazing mentor for me."

Addison Rae/Instagram

In that same interview, the "Obsessed" singer also revealed the best advice she's received from Kardashian: "Don't let everyone tell you who you are."

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"I think she always would make sure that I knew who I was and that's kind of the most important piece of advice that I've gotten from anyone," she continued. "Just really remember who you are and remember that not everyone's going to see you that way, you can't control people's perception of you, live your life and make yourself feel happy and that's kind of what matters. You'll attract people around you that are meant to be there."

Rae wasn't the only person to shower Kardashian with love on her 43rd birthday. The reality TV veteran's famous family posted heartfelt tributes for her on Instagram, as did her fiancé Travis Barker.

"My best friend, my lover, my everything," the 46-year-old Blink-182 drummer wrote alongside a black-and-white shot of the couple. "Happy Birthday @kourtneykardash I love you ♾."