Rosa Lewis (nee Dunn), the daughter of an Irish actor, John O'Donoghue, was a leading Shakespearian actress. Her sister, Marian Dunn, who was also an actress, married Marcus Clarke (q.v.) in 1869. Clarke's meeting the sisters in Melbourne is described by Brian Elliott (q.v.) in Marcus Clarke (1958).
A notice in the Argus in September 1860 refers to 'the favourite actress Rosa Dunn'. She left the stage to marry Louis Lucas Lewis, a businessman and a well-known Melbourne musical amateur, on 16 October 1863. The Lewises were not compatible and Rosa Lewis was involved in a secret relationship with Clarke, revealed later in the letters they wrote to each other in the early 1870s. Clarke's second attempt at a major novel, 'Felix and Felicitas' (unpublished), was about a clandestine love affair that ended quietly.