Agrippina the Elder, the mother of Caligula, was the granddaughter of Augustus' wife, Livia. This made her the great-niece of Tiberius, who was the stepson of Augustus. They were related by marriage through the Julio-Claudian dynasty, which held power over Rome during the first century AD.
The Empress Mother: Unveiling Agrippina the Elder - A Quiz on the Formidable Matriarch of the Julio-Claudian Dynasty