Bella Hadid pays special tribute to sister Gigi Hadid on her 25th birthday

Bella Hadid has penned down  a touching tribute to older sister Gigi Hadid in celebration of the model's 25th birthday.

The 23-year-old model took to Instagram on Friday to wish a 'happy birthday to [her] best friend, leader, teacher, [and] partner in crime.' Bella also shared adorable throwback pics of the pair.

'I wouldn’t be able to do this life without you by my side! Thank you for being the greatest big sister to me that I could ever ask for,' wrote Bella. 

Bella continued: 'I couldn’t have dreamt you up...I am so grateful for everything that you are and I celebrate you not only today, but everyday! 

For the first portrait of the photo series - shared to her 29.9million followers - Bella and Gigi can be seen posing on their farmhouse's deck, while carrying balloons in their hands.

Gigi looked noticeably makeup-free and cozy on her big day in a black turtleneck sweater, coordinating blazer, and a pair of high waisted denim jeans.