During their first winter together at St Luke's University, Bill Potts gave the Twelfth Doctor a rug as a Christmas present. (TV: The Pilot) Though he later claimed to have hated the gift, (TV: Twice Upon a Time) the Doctor kept the rug in his office, and parked his TARDIS on top of it. In return, the Doctor gave Bill photographs of her late mother, as she had none. (TV: The Pilot)