Kim Kardashian is celebrating her sister Khloe’s 40th birthday with a heartfelt Instagram tribute, just days after their latest on-screen spat on The Kardashians.

On Thursday, June 27, the SKIMS founder, 43, took to Instagram to share a sweet message for her younger sister, welcoming her to the “f***ing 40 club.”

“I feel like you have been waiting for years to finally be done with your 30s and the time has now come,” Kim wrote. “I know this will be the best decade of your life, filled with so much love and happiness!”

The reality star also reflected on their adventures together and their strong bond, calling Khloe her “best friend and sister.” Alongside the touching message, Kim shared a series of throwback photos of the pair dressed up and posing together.

Kim Kardashian shares a heartfelt message for her sister Khloe’s 40th birthday

In the photos, the sisters are seen wearing matching silver bra tops and long skirts, with Kim in grey and Khloe in black. While Kim’s long, dark hair flows down her back, Khloe opts for an elegant updo with loose front layers.

The post also includes a set of photos showing Kim lying on the ground to take pictures of Khloe during a photoshoot, showcasing their close bond.

Khloe responded to her sister’s kind words in the comments, expressing her love and gratitude. “I love you my keeks!!!!” she wrote. “You are the most incredible human being and I feel so blessed to have you by my side.”

Momager Kris Jenner also joined in on the birthday celebrations, sharing a heartfelt message for Khloe on Instagram. She praised her daughter for being a “remarkable” mom and a “joyful, happy, funny slice of life.”

Kim Kardashian shares a series of throwback photos of herself and Khloe dressed to impress

Kim welcomes Khloe to the ‘f***ing 40 club’ and wishes her a decade filled with love and happiness

Khloe responds to Kim’s birthday tribute, expressing her love and gratitude

Kris shared throwback photos of Khloe, including a black-and-white shot of the pair posing together, and a photo of Khloe as a child on a tractor truck.

Khloe also took to Instagram to reflect on turning 40, sharing a video montage of her life throughout the decades, including a rare cameo from brother Rob Kardashian. “Deeply Grateful For Every Moment,” she captioned the post.

Kim’s birthday tribute comes just hours before the latest episode of The Kardashians, in which Khloe and Kim have a heated argument. The sisters clash over Khloe’s tendency to spend all her time with her kids, with Kim expressing concern about Khloe’s well-being and encouraging her to get out more.

Khloe Kardashian reflects on turning 40, sharing a video montage of her life throughout the decades

Kim’s birthday tribute comes just hours before a new episode of The Kardashians, in which the sisters have a heated argument

Despite their on-screen disagreements, it’s clear that Kim and Khloe have a strong and loving relationship, and Kim’s birthday tribute is a beautiful testament to their sisterly bond.