A passage of Themistius (Oratio XVI, "De Saturnino") has been interpreted as identifying Claudius Antonius, Praetorian prefect of Gaul from 376 to 377 and Roman consul in 382, to be her father. However the relation is considered doubtful. In 1967, John Robert Martindale, later one of several article writers in the Prosopography of the Later Roman Empire, suggested that the passage actually identifies Antonius as the brother-in-law of Theodosius. However the passage is vague enough to allow Afranius Syagrius, co-consul of Antonius in 382, to be the brother-in-law in question.