Verity Smith
From Tardis Wiki, the free Doctor Who reference
Verity was the wife of Sydney and the mother of John Smith in the fictional backstory the TARDIS gave the Doctor when he chose to become human. They raised John on Broadmarsh Street in Radford Parade in the district of Nottingham. (TV: Human Nature) After she and her husband died the family maid, Martha Jones, continued to serve John. (TV: The Family of Blood)
Behind the scenes
John's parent's names Verity and Sydney were a tribute and reference to Verity Lambert and Sydney Newman, both essential to the making of Doctor Who.
