Malcolm Wainwright was the grandson of Kathy Nightingale and Ben Wainwright.
Malcolm delivered a letter from his deceased grandmother, which she had written on 7 February 1987, to Sally Sparrow in 2007. The letter explained that Kathy had been sent back in time to Hull on 5 December 1920 by a Weeping Angel. The Kathy in the present day was secretly witness to the delivery before she disappeared, and so knew when and where to send her grandson to deliver the letter.
Malcolm's great-uncle was Larry Nightingale, who was Kathy's brother. (TV: Blink)