Nero Claudius Drusus
Nero Claudius Drusus, usually called simply Drusus or Drusus I (38 - 9 BC) was the younger son of Livia, wife of Augustus Caesar, and her first husband, Tiberius Claudius Nero (although he was born after Livia had divorced him and married Augustus). He married Antonia Minor, the daughter of Mark Antony and Augustus's sister, Octavia. Their children were Germanicus, Livilla, and the future Emperor Claudius.
Drusus, like his brother Tiberius, was a skilled general, campaigning in Germany and along the Danube. He died of wounds suffered on campaign against the Marcomanni. Augustus later wrote a biography of him (which does not survive).