Charlotte Benton

John Benton's sister was the younger sister of John and Chris Benton.

Biography
John called her his "kid sister", and often met up with her. During his days with UNIT, he was going to meet her at eight o'clock outside the Chinese takeaway.

John was planning to take her to a dance at the Palais, and phoned her from Devesham Control to remind her not to be late. (TV: The Android Invasion)

Behind the scenes

 * John Benton's sister is never seen, only referred to; and is also never identified with a proper name on-screen.
 * John Benton's sister is not seen or mentioned in Wartime, so it is perhaps best left to personal preference as to whether Mrs. Benton was pregnant at the time of her husband's death or she remarried at some point afterwards.