Lucky to be your baby sister: Bella shares childhood pics with Gigi on b'day

American model Bella Hadid on Saturday wished her sister-model Gigi Hadid on her 27th birthday. Sharing a few childhood pictures on her Instagram handle, Bella wrote, "Thank you for being born so that I could be born that was very sweet of you." "Thank you for being...best sister, mom, daughter...ever...I feel so lucky to be your baby sister," she added.