Dr. Who's reality (Dr. Who and the Daleks)

One of the possible parallel universe versions of the Tenth Doctor drawn up by Gabby Gonzalez's "magic" notebook resembled (COMIC: Four Dimensions) the version of Dr. Who who had a niece called Louise and a granddaughter called Barbara in addition to his granddaughter Susan. This suggested that his reality was a parallel universe relative to the Tenth Doctor's. (NOTVALID: Dr. Who and the Daleks, Daleks' Invasion Earth 2150 A.D.) However, other accounts of how this Dr. Who related to other versions of the Doctor existed. (PROSE: Unnatural History, The Five O'Clock Shadow, etc.)

Relation to other realities
During the Last Great Time War, the Time Lords were aware of multiple, alternative accounts of the Doctor's first encounter with the Daleks, all of which involved Ian Chesterton. Opinions varied as to whether these accounts were apocryphal or evidence of Dalek activity in parallel dimensions. (AUDIO: Sphere of Influence, PROSE: Dalek Combat Training Manual)

Behind the scenes

 * The Road to Conflict, a continuation of The Daleks, was written to lead into Daleks' Invasion Earth 2150 A.D.. The Daleks, which followed the Daleks without the Doctor or Dr. Who, began with an account of their their creation at the hands of Yarvelling, an account which was contradicted by the introduction of Davros in the television series.
 * In an interview in DWM 490, Steven Moffat proposed that Dr. Who recklessly altering Time to change the outcome of the bank robbery at the end of Daleks' Invasion Earth 2150 A.D. caused him to accidentally restart the universe, rewriting himself into a Time Lord and losing his family name.