10 Unanswered Doctor Who Mysteries
3. What Happened To Susan And Is She A Timelord?
Directly linked to the question of The Doctor possibly having a family and children of his own, comes the question regarding his granddaughter and first companion, Susan. Taken on its merits, it would be fair to assume that Susan would in fact be a Timelord herself, having grown up on Gallifrey alongside the Doctor.
This is another mystery that has come back to life with the Timeless Child revelations, and make us ponder exactly who, and where Susan may be. The question of her being a Timelord relates directly to her parentage, with the possibility that she is a 'hybrid' of sorts a very interesting prospect indeed. This also opens up the option of Susan being the prophesised Hybrid that would bring destruction upon Gallifrey and the Timelords, however unlikely.
Susan became the first companion in Who history to leave the TARDIS when she was left behind on Earth with her new love David. The Doctor bizarrely never tried to make contact after this moment, although comments made by Doctors of the NuWho era infer that she may have died during the Time Wars.
There is the possibility that Susan has regenerated on a number of occasions and had no affinity to the Timelords at all. Or maybe the Matrix wasn't telling the whole truth, and it was in fact Susan who was the Timeless Child, with the Doctor realising this and helping her escape. The possibilities are endless.