Gigi Hadid gets upstaged by younger sister Bella in keyhole dress at Global Lyme Alliance gala to support mom Yolanda Foster

Gigi Hadid and her sister Bella are both gorgeous models making names for themselves on the fashion runway.
Bella seemed to be grasping most of the spotlight on Thursday as the siblings attended the Global Lyme Alliance 'Uniting for a Lyme-Free World' Inaugural Gala in New York City in support of their mom Yolanda Foster.
While Gigi was certainly elegant in a strapless ivory gown that fell to the floor and pooled around her flat beige shoes, Bella played up her vamp appeal in a skintight black number with a daring cut-out.
But Yolanda's moving speech, in which she disclosed that Bella and  Anwar had also been 'diagnosed with chronic Lyme disease in early 2012,' was the ultimate shocker.