Nicholai "Nicky" Olivia Hilton (born October 5, 1983 in New York City, New York, USA) is an American fashion model, socialite, celebutante, entrepreneur, heiress, and fashion designer. She shares her nickname with her grandfather's brother, Conrad "Nicky" Hilton, who died fourteen years before she was born. She is the younger sister of Paris Hilton.
Source : Wikipedia.com