Kim Kardashian's birthday Instagram for Kourtney includes a hilarious joke.

Kim K Brought Up Her Fistfight With Kourtney In Her Birthday Post For Her Sister

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Kim Kardashian is making jokes about the infamous fistfight with Kourtney that shocked fans in the March 26 premiere of Keeping Up with the Kardashians Season 18. The joke, however, is out of love. Kim may be trying to put some of the bad blood behind them, because she wrote a heartfelt tribute. Kim Kardashian's birthday Instagram for Kourtney joked about their fight, but it isn't how it sounds.

ICYMI, the altercation between Kim K and her sister Kourtney raised a ton of eyebrows and caused plenty of noise on social media. The Season 18 premiere episode of Keeping Up with the Kardashians was a lot to unpack, as it ended with Kim and Kourtney throwing punches at one another when an argument got out of hand. After it aired, Kim made an appearance on The Tonight Show: Home Edition with Jimmy Fallon on Monday, March 30 and explained the situation, saying, "I feel like it's been a lot of built up resentment from Kourtney." It was some real drama, and was even a lot for viewers to handle. Kim admitted to Fallon the throwdown caused production of KUWTK to halt for a week. "Everyone was really shook for a minute," she said.

All things aside, Kim K posted on Instagram for Kourtney's birthday on Saturday, April 18 in light of recent events. "Happy Birthday @kourtneykardash I had to find some good throwbacks to celebrate you today! I remember these moments so vividly," Kim wrote alongside some sweet photos. She continued, "I love your strong will to do whatever makes your soul happy, the love you have for you children and for being the best big sister. I couldn't be more thankful for our memories together."

She finished the post by referencing the fight: "You pack a mean punch I love you so much and can’t wait until this is all over so we can celebrate together." Since she joked about the punches, it seems that Kim K may be trying to mend her feud with her sister.

Other Kardashian-Jenners posted tributes for Kourtney's 41st birthday with some sweet photo moments of their family. Khloé shared a post, writing, "Happy birthday my beautiful @kourtneykardash!!! In any lifetime I would have found a way to have you in my life forever," she wrote. "I can’t imagine my life without you, nor would I ever want to imagine that. You and I have an incredible, rare bond that no matter what, it can never be broken," she continued. "You are my best friend, one of the rare few I can count on most in my life," she gushed.

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Kris Jenner posted a mix of old and recent photos for her daughter's birthday. "Happy Birthday to my beautiful daughter Kourtney!!!! I love your amazing zest for life and the way you love your kids and all of us around you," she wrote. "Thank you for teaching us to slow down and smell the roses. You are an amazing daughter, sister, friend, and mommy."

And Kendall Jenner also joined in. On her Instagram Stories, she posted a birthday thread. "Happy birthday to my adventure buddy," she wrote. Her Stories also revealed a string of cars lined up outside of Kourtney's home, for a "quarantine birthday party." Those close to the celeb brought balloons, honked their car horns, cheered, and wished her a birthday from a distance, including Kendall.

Check out Kourtney's IG Stories to see what she's doing while celebrating at home.