Mr Barnabas was the name of Sarah Miller's teddy bear. She held onto it when she was buried during an air raid. Both she and the bear were rescued. (PROSE: Tell Me You Love Me)
Behind the scenes[]
In 2022, Scott Matthewman expressed on Twitter how it was "slightly mad" that there was a Tardis Wiki page dedicated to the bear, and that, jokingly, that he hoped Mr Barnabas would cameo in the sixtieth anniversary specials.[1]