Kim Kardashian is remembering her dad on what would have been his 73rd birthday.
The mother of two took to Twitter to share a sweet family photo from her childhood, alongside a touching message thanking the late Robert Kardashian Sr. for "everything."
WATCH: Rob Kardashian Shares Sweet Throwback Pics on Dad Robert Sr.'s Birthday: 'Wish You Were Here to Meet Dream'
"Happy Birthday dad! I love this family photo. I love our family," Kim wrote. "Thank you for EVERYTHING. I'm so grateful you are my dad!"
The 36-year-old reality star also posted that she had found a three-page letter her dad wrote her after high school, and how she hopes to write similar letters for her children, 3-year-old North and 1-year-old Saint West.
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Kourtney Kardashian, meanwhile, took to Instagram to share a throwback pic of herself as a baby -- commenting on her dad's amazing moustache -- while Kris Jenner posted the same family photo as Kim, writing, "There’s not a day that goes by that we don't miss you."
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The Kardashian family also paid tribute to Robert in December, celebrating his life and memory at the Angel Ball in New York City.
See more in the video below.