Joshua (Forest of the Dead)
From Tardis Wiki, the free Doctor Who reference
Joshua was the false son of Donna Noble and Lee McAvoy. In reality, he and his twin sister, Ella, were basic computer programs that would simulate the children of those saved into the Data Core of the Library. There was only one girl model and only one boy model, so there were many copies. Identical children were seen at a playground. River Song read bedside stories the two children, as well as CAL herself. (TV: Forest of the Dead)
