"Happy birthday lil sassy northie!! We love you!" commented Kimora Lee Simmons.
"Happy birthday North! ♥️" commented Kim's longtime friend and makeup artist Mario Dedivanovic.
"Awww HBD little Northie!" wrote family friend and hairstylist Jen Atkin.
Kim's brother Rob Kardashian posted on his Instagram page a throwback photo of North with the family's dog Sushi.
"Happy birthday North!! 🎉❤️ #NorthWest," he wrote.
Grandma Kris Jenner also shared on Instagram a slew of pics of North, including a couple showing both of them together, one of the little girl rocking a shimmering green outfit and sunglasses, a few pics of her with her cousin Penelope Disick, who will turn 7 next month.
"Happy Birthday to my little Angel Northie!!!!" Kris wrote. "What a bright light you are and such a blessing to our family!! Your magic and sunshine lights up every room and I adore how creative and smart you are. You are so kind and loving to everyone you know and have a beautiful heart and soul...I love you so much precious North and it is a pleasure and a privilege to be your Grandmother. I love you ❤️ Lovey xo #HappyBirthdayNorth."
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