10 Unanswered Doctor Who Mysteries
5. What Happened To Jenny?
The character of Jenny was the 'child' of The Doctor who was 'created' from the Doctor's DNA in the episode titled The Doctor's Daughter. Appearing in the 6th episode of David Tennant's final full season, Jenny was created as a young female soldier as part of a war between humans and native species The Hath.
The extremely innovative and exciting plot point that is Jenny strangely hasn't been addressed since this episode, leaving many pondering where she is now. The Doctor had assumed she died, having not seeing her eventual regeneration and blast off into space for further adventures.
So where could Jenny be? You would think the young lady would be keen to track down her father, although it is a very big universe, so she could have just failed to do so yet. Adding to the mystery is Jenny's ability to regenerate, meaning the Doctor may have met her without knowing it. Why Jenny would withhold her identity would need to be explained, but her ability to change her appearance opens up a range of possibilities.
The other possibility is that Jenny can't fully regenerate, with the ability to use some regenerative energy without the ability to take a new form. Georgia Tennant(formely Moffett) has recently returned to the role of Jenny as part of the Big Finish audio plays, so having her return to tie up this story arc would be great to see and could allow for an emotional reunion.