Pudsey
From Tardis Wiki, the free Doctor Who reference
This topic might have a better name.
Pudsey Bear as the Doctor describes several different Pudseys in Looking for Pudsey.
Talk about it here.
Pudsey Bear was a temporary companion to the Twelfth Doctor and Clara, he helped defeat Sontarans, Daleks, Colony Sarff and the Mire. (NOTVALID: Doctor Who Game Maker)
The Twelfth Doctor was later contacted, to help in search for former companion, by Eddie Redmayne. (NOTVALID: Looking for Pudsey)
Behind the scenes
He was added as a companion for one week during Children in Need.
More info at Children in Need.