Kim shared several photos and videos from the celebration on Instagram, including a video of herself with Khloe and Tristan.
The 37-year-old star was all smiles as she asked Tristan to unblock her on Instagram.
"Alright, guys, so what do you think? It's Khloe's birthday. Do you think I should ask this guy to unblock me?" she said in the clip. "For Khloe's birthday, will you please unblock me?"
Kim had said in an interview with "Live! with Kelly and Ryan" in May that Tristan blocked her on Instagram after she commented on his "messed up" situation with Khloe.
Khloe welcomed True in April following reports Tristan cheated during her pregnancy.
"So, was that a yes?" Kim asked Tristan in another clip from the party. "I'm unblocked, guys!"
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Kim also wished Khloe a happy birthday in a post on Instagram. She shared a throwback photo of herself with Khloe, True and her own daughter Chicago West.
"Happy Birthday to one of my favorite souls on this planet! @khloekardashian," the star wrote.
"This year you have shown strength like none other. I admire you for always following your heart. I love seeing you as a mom and can't wait for the years ahead. Let's celebrate you today! I love you to infinity!"
Khloe's mom, Kris Jenner, was among those to also wish the star a happy birthday.
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