Josephine Grant, later Jo Jones, is a companion of the Third Doctor. A civilian working for UNIT, Jo is first assigned as the Doctor’s assistant to help him in the laboratory on the Brigadier’s orders, but later becomes the Doctor's companion. Despite serving as a companion only to the Third Doctor, Jo has also met the Second and Eleventh incarnations of the Doctor. When the Doctor is away and Jo is left on own for a while, she meets activist and mycologist Professor Clifford Jones and falls in love with him. After marrying Clifford, Jo resigns from UNIT and leaves the Doctor. With Clifford, she travels the world extensively and has several children and grandchildren.