He had a paternal half-brother called Marcus Claudius Ummidius Quadratus, from his father's first marriage, who was adopted by the Roman Consul Marcus Ummidius Quadratus Annianus, a nephew of the Roman Emperor Marcus Aurelius.
He had a paternal half. Brother called Marcus Claudius Ummidius Quadratus. This was from his father's first marriage. His father's first marriage was adopted by the Roman Consul Marcus Ummidius Quadratus Annianus. The Roman Consul Marcus Ummidius Quadratus Annianus was a nephew of the Roman Emperor Marcus Aurelius.