Agrippina the Elder
Drusus was born in around AD 8 to Germanicus and Agrippina the Elder. Drusus' paternal grandparents were Nero Claudius Drusus (Drusus the Elder) and Antonia Minor, daughter of Mark Antony and Octavia Minor. His maternal grandparents were Marcus Vipsanius Agrippa, a close friend of Augustus, and Augustus' daughter Julia the Elder. Drusus had eight siblings: four brothers (Tiberius and Gaius Julius, who died young; Nero Caesar; and Gaius, nicknamed "Caligula"), three sisters (Agrippina the Younger, Julia Drusilla, and Julia Livilla), and a brother or sister of unknown name (normally referenced as Ignotus).