Question: Emilia Rose Elizabeth Fox, is an English actress, known for her role as Dr. Nikki Alexander on BBC crime drama "Silent Witness", having joined the cast in 2004 following the departure of which Northern Irish actress, well known for her television roles, including Heather Black in the Channel 4 soap opera "Brookside"?
Sentence (from "Emilia Fox"): Fox is now the longest serving cast member since the departures of Tom Ward in 2012 and William Gaminara in 2013.
Relevant evidence: No