Gigi Hadid gushes over Zayn Malik as she pens heartfelt birthday tribute for him

Fashion icon Gigi Hadid is gushing over her beau Zayn Malik on his birthday.

As the former One Direction dreamboat rang in his 28th birthday, his ladylove turned to her Instagram and posted a heartfelt tribute for her ‘baby daddy.’

"Team No Sleep!" she wrote. "Happiest birthday to our Zaddy baba. So special. Love you long time, thank you for makin me a mamma to the best girl ever. Wish you the best every single day,” she added.

Alongside the note, she posted an unseen photo with her boyfriend and an illustration of the singer cradling his daughter.

The two have purposely been keeping their relationship strictly private as they have been dating on and off since November 2015.