Her maternal grandparents were Abraham "Abe" Schneid and Sunny (née Schneider).
[citation needed] She attended The Buckley School in Sherman Oaks, California, after attending the American Academy of Dramatic Arts (AADA) in New York, New York.
In 2005, Mirojnick began appearing in uncredited and minor film roles.
In 2010, she won the lead role in the independent film Kill the Habit.
From 2011–2014, she made a number of guest appearances in network television series including Person of Interest, Blue Bloods and Grey's Anatomy.