Gigi and Bella Hadid are famous sisters. The light, makeup, and angles are different in each photo and one can never be sure without confirmation from the person herself. However, I would say with relatively high confidence that Bella has undergone a rhinoplasty to have her dorsum reduced and the tip of her nose rotated upward and refined. Before, her drooping tip has been corrected, and the nose is overall shorter. For Gigi, it is less clear.
