Kourtney shared a throwback photo on Instagram of herself with her dad and Kim at what appears to be a Christmas celebration. Kourtney wears a white dress with a tiered skirt, while Kim sports a frilly pink dress.
"Daddy's girls," she captioned the picture. "Happy Birthday Daddy. I miss you every day. Kim wasn't as happy about her dress as I was."
Kim said in a post on her own account that she celebrated by ordering her dad's favorite cake.
"Happy Heavenly Birthday Dad! Miss you so bad. I ordered your favorite Ralph's cake to celebrate! Love you forever!" she wrote.
Rob, meanwhile, shared a throwback photo on Twitter of himself with his dad.
"Happppy Birthday Dad!!" he wrote, adding smiley face and angel emojis.
Robert died at age 59 in September 2003 after battling esophageal cancer.
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