On April 18, 2018, Kourtney Kardashian turned 39 years old. And as a member of the first family of reality TV, her big day was celebrated heavily on social media.

Matriarch Kris Jenner was the first to post a tribute to Kardashian. She uploaded a photo of herself, wearing a yellow polka dot dress and matching hat, holding a baby Kourtney, who wears a white ruffly dress and coordinating cap and looks thoroughly unamused in her current situation. "Happy birthday @kourtneykardash!!!! My first born, my gift from God, my amazing precious blessing!! You have given me so much joy and love and beautiful immeasurable experiences and memories since the day you were born and I thank God every single day that he chose me to be your mom," Jenner wrote. "I'm so proud of you...you are the most amazing mom, sister, auntie, and daughter and I love you with all of my heart forever and ever [...] Mommy xo."

Kim Kardashian West, who's only 18 months younger than the birthday girl, posted her own photo with Kourtney: a shot of the duo lounging on a daybed during their recent Turks and Caicos vacation. "Happy Birthday to my friend I've had the longest in my life! Wouldn't know what to do without you! Have the best birthday ever!!!!" she captioned the pic. Younger brother Rob Kardashian responded to Kardashian West's post via Twitter—"You guys are so cool lol," he quipped—before uploading a throwback shot of Kim and Kourtney posing with dad Robert Kardashian, Sr., which he captioned, "Happy Birthday to my oldest and wisest Sister ! I LOVE YOU so much!!! I am so Thankful for you and God Bless You with another amazing year! Love[,] Bob."

Though Khloé Kardashian has yet to post about her older sister's birthday, Kourtney shared a photo on her Instagram Story on Tuesday of a cake covered in roses, chocolate-covered strawberries, and a note wishing her a happy birthday, revealing in the caption that it had come from Khloé, who is probably too busy with newborn daughter True Thompson at the moment to craft a heartfelt b-day post for Kourtney. "It's my birthday tomorrow !! thank you @khloekardashian," Kourtney wrote on the photo of the cake, before posting another not-so-subtle reminder about her special day: a photo of her and youngest sister Kylie Jenner at Coachella last weekend, captioned, "it's my birthday tomorrow." Kylie and big sis Kendall Jenner have yet to post their own public tributes to their eldest sibling, but we're sure they're forthcoming.

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