 It was also through his mother's side of the family that he was the nephew of Honorius and first cousin to Theodosius II (the son of Honorius' brother Arcadius), who was eastern emperor for most of Valentinian's life.Valentinian had a full sister, Justa Grata Honoria, who was probably born in 417 or 418 (the history of Paul the Deacon mentions her first when mentioning the children of the marriage, suggesting she was the eldest).His mother had previously been married to Ataulf of the Visigoths, and had borne a son, Theodosius, in Barcelona in 414; but the child had died early in the following year, thus eliminating an opportunity for a Romano-Visigothic line.