It looks like Christie Brinkley‘s little girl isn’t so little anymore! The supermodel took to Instagram on Tuesday, July 2, to share the sweetest words titled “Sailor’s Happy Birthday Poem” and old childhood pics in honor of her youngest daughter Sailor Brinkley-Cook‘s 21st birthday.

In the poem, the 65-year-old began, “21 years around the sun you’ve learned a thing or two. It started with little you, wanting to do everything your brother and sister could do!” she wrote, mentioning Sailor’s older siblings, stepsister Alexa Ray Joel, 33, and brother, Jack Brinkley-Cook, 24.

Throughout the heartwarming essay, Christie gushed about her daughter Sailor, who was described as a “natural leader” and “kind to one and all.” The National Lampoon’s Vacation actress also pointed out a few of her mini-me’s accomplishments, which include making “clothes look terribly chic as model for IMG [modeling agency], Sports Illustrated and [photographer] Bruce Weber.”

The proud mama concluded the essay, writing: “Yes, in 21 years you have learned a thing or two. Especially how to make the world a better place just by being being you! Sail on, Sail on, Sailor! I love you soooooo much!”

The next day, Christie shared a series of pics from the birthday girl’s celebration on July 3. “And just like that my little sunflower is 21!” she wrote in the caption. “Sailor, may you breeze through this next year with the wind at your back and your sails filled with laughter, adventure and love! @sailorbrinkleycook.”

South Fork Natural History Museum Honors Christie Brinkley
Christie and her children, Sailor, Alexa Ray and Jack in 2012. Sonia Moskowitz/Getty Images

The blonde beauty also took a moment to reminisce about her daughter’s birth. “Sailor had her first big adventure in the first minute of her life! As the Doctor handed her to me for her first hug … the bottom half of the table we were on broke … turning our bed into a slide!!!!” she hilariously recalled. “I held tight to my baby girl as we slid off right onto the Doctor! Talk about comedic timing and a memorable first entrance! That’s my @sailorbrinkleycook.”

The Vegas Vacation actress’ loving tribute comes as no surprise considering she and Sailor have an incredible mother-daughter relationship. This past February, Christie and Sailor walked the runway together at New York Fashion Week for the first time ever! The adorable duo was even spotted giving high-fives as they passed each other on the catwalk during Elie Tahari’s show.

We love their bond!