Erica McDermott (born April 26, 1973) is an American actress, perhaps known best for her supporting role as Cindy "Tar" Eklund, the sister of the lead character, in the David O. Russell film The Fighter (2010).
Having trained as a registered nurse, however, she initially focused on her career in the medical profession and raising her family.
[1] In 2008, McDermott decided to launch her acting career, starting with an appearance in The MOMologues for a school fundraiser.
She was soon cast, at the age of 36, as Mark Wahlberg's character's sister in the David O. Russell film The Fighter (2010).
[3] In 2015, McDermott played Benedict Cumberbatch's wife in the critically acclaimed crime drama film Black Mass (2015).