Kamala Harris' niece Meena, 36, wore The Vampire's Wife gown this week
Stepped out in emerald green metallic dress for the Celebrating America event
Kate Middleton, 39, donned the same £1,595 dress last March in Dublin last year
Princess Beatrice, 31, wore silk-blend lamé gown to Ellie Goulding's wedding
Holly Willoughby and Alexa Chung have also worn the garment in recent years
Celebrity stylist said it has 'maximum impact' but is 'easy to wear' and 'versatile'