Happy 23rd birthday, Anastasia Karanikolaou!
Kylie Jenner took to Instagram on Tuesday to celebrate her best friend's birthday, and alongside a series of photos of the duo, she described Stassie as the "rarest of all time" and "truly a gift to this world."
Even more sweet, Kylie called Stassie "the best aunty to my babygirl," Stormi Webster.
"i can't believe we are celebrating your 23rd birthday," Kylie continued. "i cherish every year we've spent together and i thank God for putting you in my life. i wouldn't be able to do it without you. i have your back till the end of time. today and every day.. we celebrate you."
The carousal of photos included a number of throwbacks, starting with a snapshot from last Halloween, when the two dressed up as Playboy bunnies. There's also a pic from Stassie's last birthday, in which both she and Kylie are wearing matching knitted Chanel crop tops while golfing.
In addition to Kylie's post, Stassie uploaded a photo from the previous night, when Kylie and a few other friends celebrated her birthday in matching "Stassi turns 23" sweatshirts.
In honor of the birthday girl, take a look back at some of her cutest photos with BFF Kylie by scrolling through the below gallery!
Happy birthday, Stassie!