Livilla

Claudia Livia (Classical Latin: CLAVDIA?LIVIA; c.?13 BC C AD 31) was the only daughter of Nero Claudius Drusus and Antonia Minor and sister to Roman Emperor Claudius and general Germanicus, and thus paternal aunt of emperor Caligula and maternal great-aunt of emperor Nero, as well as the niece and daughter-in-law of Tiberius. She was named after her grandmother, Augustus' wife Livia Drusilla, and commonly known by her family nickname Livilla ("little Livia"). She was born after Germanicus and before Claudius. She was twice married to the potential successor in the Julio-Claudian dynasty, first to Augustus' grandson Gaius Caesar (died AD 4) and later to Tiberius' son Drusus the Younger (died AD 23). Allegedly, she helped her lover Sejanus in poisoning her second husband and died shortly after Sejanus fell from power in AD 31.

from Wikipedia