Tristan Thompson wishes ex-girlfriend Khloé Kardashian happy 40th birthday

Tristan Thompson wished his "best friend" and ex-girlfriend Khloé Kardashian a happy 40th birthday on Thursday.

The basketball player took to his Instagram Stories on Thursday to mark the reality star's milestone birthday by posting a series of pictures of him, Khloé and their children True, six, and Tatum, who turns two this summer.

Across the posts, the sportsman wrote, "Happy Birthday Khloé!!... You are the best mom... You are my best friend."

He concluded his celebration by posting a picture of Khloé with his younger brother Amari, who he is the legal guardian of.

"And the most incredible human being I've ever met," he captioned the last post.

Khloé shared the last slide on her Instagram Stories and added, "Thank you! I appreciate this! I love my Amari."

The Kardashians star, who dated Tristan on and off from 2016 to 2021, celebrated her birthday on Thursday with a family pool party. She also posted a video clip showing her blowing out the candles on a birthday cake as her friends and family sat around the table.

Her mum Kris Jenner marked the milestone on Instagram by gushing about "the most amazing daughter" and her "beautiful, delicious angel".

"I am not sure what I did to deserve you, but I thank God every single day for the beautiful blessing of being your mommy... you are one of the most wonderful loves of my life, and I cherish each and every glorious memory we have ever made," she wrote.

Meanwhile, Khloé's older sister Kim Kardashian welcomed her "best friend" into the 40s club.

"I know this will be the best decade of your life filled with so much love and happiness!" she captioned her post. "I'm so excited for you to experience this because I know how good it is, and no one deserves this more than you! What a crazy life we live! I couldn't do it without you by my side!"

Their older sibling Kourtney Kardashian echoed that sentiment by writing, "Truly don't know what I would do without you... What a ride it's been and continues to be with you by my side. I miss you every second you're not with me."