Drusus Julius Caesar
Tiberius married Vipsania Agrippina, the daughter of Augustus' close friend and most famed general, Marcus Vipsanius Agrippa. He was appointed to the position of praetor, and was sent with his legions to assist his brother Drusus in campaigns in the west. While Drusus focused his forces in Gallia Narbonensis and along the German frontier, Tiberius combated the tribes in the Alps and within Transalpine Gaul, conquering Raetia. In 15 BC he discovered the sources of the Danube, and soon afterward the bend of the middle course. Returning to Rome in 13 BC, Tiberius was appointed as consul, and around this same time his son, Drusus Julius Caesar, was born.