Kate graduated high school a year early. She was accepted at the prestigious NYU Tisch School of the Arts but deferred for 3 consecutive years due to acting and singing.

She is the great-granddaughter of the founder of the New York Giants, Timothy Mara and Art Rooney, founder of the Pittsburgh Steelers. She often sings the national anthem at Giants home games.
Has older brother, Dan. Grew up in Bedford, New York. Granddaughter of Wellington Mara. Ranked #43 on the Maxim magazine Hot 100 of 2007 list. A skilled jazz/tap/ballet dancer. Her younger sister Tricia Mara is also an actress.