Jack Carstairs was a companion of the Tenth Doctor during one of his adventures.
Orignally born on Earth Jake Carstairs along with his twin sister moved to Colony planet Chelsea 426 which orbited Saturn. His parents ran a Hotel there and they assigned them to do chores. He often dreamed of flying into space one day. When he was 14 years old he met the Doctor. This coincided with the Rutan invasion of Chelsea 426. He, the Doctor, Vienna and His Mother went to the opening presentation of the flower show there. His mother was affected when Professor Wilberforce activated a plant which put her under the control of the Rutan Host. He and his sister where evacuated with the doctor and hid in his Tardis along with a stranger known as the Major. He later stopped the Sontarans from destroying earth. After the invasion was stopped his mother was freed from the rutan's and he was rejected from travelling with the doctor. But the Doctor later reassured him that when he was older he would see the universe as a starship pilot. (NSA: The Taking of Chelsea 426)
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