Born: April 12, 1929; February 18, 2013.

Elspet Gray, who has died aged 83, was an actress known not only for her guest-star roles in television series such as Fawlty Towers, Blackadder and Doctor Who, but also for her campaigning work on learning disabilities with her husband Brian Rix, the actor and former head of Mencap.

Anyone who regularly watched television in the 1970s and 1980s will remember Gray. She appeared in one of the most celebrated Fawlty Towers episodes as a psychiatrist who becomes increasingly baffled by Basil's erratic behaviour. She was also Phyllis Bristow in Tenko, the BBC drama about women prisoners of war during the Second World War, and appeared in Doctor Who as the Time Lord, Chancellor Thalia in the Peter Davison story Arc of Infinity. Blackadder fans will also remember her as Rowan Atkinson's mother Queen Gertrude in the first series of the comedy.

She was born in Inverness in 1929 and was educated in Hastings and at a convent in India where her father worked for a bank. She returned to Britain to train at Rada and met her future husband Rix when she auditioned for him (he was running a repertory company in Margate).

From the start, they were an unconventional couple, living together at a time when that was not done. They went on to work together in many stage farces, their first hit being Reluctant Heroes, a comedy set in an army boot camp, which went into the West End and became a film in 1951.

At this point, Gray left the profession for a while to raise her first child Shelley, who had Down's Syndrome. Shelley lived at home for a number of years and then in residential care and her disability inspired a lifelong commitment by Gray and Rix to campaigning on disability issues; Rix presented a BBC series on the subject and became secretary general of the learning disability charity Mencap.

Gray went on to have three other children but did eventually return to the stage in the late 1950s, appearing in several of the farces for which Rix was now famous. In the 1970s she began to work more in television, where she became known as reliable support in ongoing series. Over the years she appeared in Inspector Morse, Poirot, Dr Finlay and others. She also played Felicity Kendal's mother in her sitcom Solo, which was written by Carla Lane.

Gray also occasionally worked in films, most notably as the mother of the first bride in Four Weddings and a Funeral. She became Lady Rix when her husband was made a life peer.

She is survived by her husband, two sons, a daughter and grandchildren. Shelley died in 2005.