Penelope Gate's first son

From Tardis Wiki, the free Doctor Who reference

When they met during her first time-travel adventure, Penelope Gate told Chris Cwej that she and her husband had had a son until three years prior, when the baby had died, less than a year old. (PROSE: The Room With No Doors)

Behind the scenes[[edit] | edit source]

The Infinity Doctors and The Gallifrey Chronicles would later reveal Penelope Gate as the Doctor's mother, meaning that this first, human child would have technically been a half-sibling of the Doctor's.