Sida
Sida was Steven Taylor's granddaughter and later President of the unnamed planet he had settled on.
Biography
After he was deposed as king, Sida visited her grandfather to listen to his stories about travelling with the First Doctor and Dodo Chaplet. (AUDIO: The War To End All Wars)
She later took Steven to see the jar of the Doctor's consciousness as it wanted to run for election. Steven told her the story of how he and the Doctor met Benjamin Franklin to show how the Doctor would never seek power in such a way, and therefore that he shouldn't be trusted. She found out that the consciousness of the Doctor killed a boy in one of his experiments. She was told by the jar to run for election, which she won, becoming the president. (AUDIO: The Founding Fathers) During her presidency, Sida gave Steven money to create a radio-telescope.
Three years later, Steven invited Sida to his secluded house in the mountains, where she helped him to contact the First Doctor. This was actually part of a plot by a Vardan they had defeated years ago to reconstitute itself. After utilising the help of the Doctor and his mind copy, the Vardan was destroyed, but not before causing a lot of damage to the planet, which Sida covered up as a natural disaster. Sida then convinced Steven to return to public life to help with the rebuild. (AUDIO: The Locked Room)