Anthony Tyler
Rose's little brother
Anthony was only an infant in the show (as far as anyone knows).
In Legacy, he is nearly an adult and works with his mother on an unofficial basis since officially he is still an toddler. When the Tyler's relocated to the main universe, Tony required an explanation like they did. Since he was still their son, Gwen suggested that officially Tony be born approximately a year after Pete and Jackie came back from the dead with the same day of birth as he did in their universe. It was grudgingly agreed to, but then they had the problem of explaining who he was or where he was from.
It was Alex's suggestion that since it was common knowledge within UNIT and Torchwood that the Tyler's were directly associated with the Doctor that Anthony was another, future, Companion and his involvement in "present day" was due to the Doctor's direct interference.
This was agreed on by his parents and Tony as the best possible outcome. Alex then took the young man aside and offered him a conditional, but open, position with his Torchwood in the 23rd century. Tony accepted.
In Legacy, he is nearly an adult and works with his mother on an unofficial basis since officially he is still an toddler. When the Tyler's relocated to the main universe, Tony required an explanation like they did. Since he was still their son, Gwen suggested that officially Tony be born approximately a year after Pete and Jackie came back from the dead with the same day of birth as he did in their universe. It was grudgingly agreed to, but then they had the problem of explaining who he was or where he was from.
It was Alex's suggestion that since it was common knowledge within UNIT and Torchwood that the Tyler's were directly associated with the Doctor that Anthony was another, future, Companion and his involvement in "present day" was due to the Doctor's direct interference.
This was agreed on by his parents and Tony as the best possible outcome. Alex then took the young man aside and offered him a conditional, but open, position with his Torchwood in the 23rd century. Tony accepted.