Gigi Hadid: Bella Hadid is my 'inspiration'

Gigi Hadid has praised her younger sister Bella as an "inspiration".

The 22-year-old model took to Instagram on Monday (09.10.17) to celebrate her sister and fellow model hitting the milestone age of 21, and in a sweet tribute, she claimed she is "so so proud" of her "forever cool" sister.

Posting a throwback picture of a young Gigi feeding Bella her bottle, she wrote: "HAPPY 21st BIRTHDAY MY ANGELIC SISTER @BELLAHADID !!! There are no words for how much I love you. You know I've been trying to protect u from the world since day one, and 21 years later u comfort and inspire me more than you'll ever know. You have always marched to your own drum, and you make me so so proud. You are loving, kind, driven, perseverant, and forever cool af. You have a power to empathize with everyone & love always, and you make so many people happy in doing so! So excited to celebrate tonight - Cheers to YOU Bella Kai Kai I LOVE U MY LIL SISSYPOP "

The post comes after the blonde beauty - who is in a relationship with Zayn Malik - took to the photo sharing website the day previous to remind her followers that her "forever bestie" would be turning 21 soon.

She wrote: "TOMORROW WILL BE 21 YEARS SINCE I MET MY FOREVER BESTIE @bellahadid (me wearing all red on your actual day of birth is MAJOR and possibly the reason it's your favorite color) "

Gigi isn't the only member of the Hadid family to send her well wishes to Bella on social media either, as their younger brother Anwar, 18, dubbed the brunette as "the best sister ever".

He wrote: "@bellahadid love you so much my sister!! Happy 21st i love you forever!! Thank you for being the best sister ever and for teaching me everything i need to know about life itself. "