Julia Antonia Minor ("the younger") (30 January/31 January 36 BC - May-October 37 AD) was the daughter of Mark Antony and Octavia.

She married Drusus -- the son of the empress Livia and brother of the emperor Tiberius -- and their children were Germanicus, Livilla, and the emperor Claudius. She was the grandmother of Caligula and Agrippina the Younger, and the great-grandmother of Nero.

She never remarried after the death of her husband in 9 BC. When her son Germanicus died in 19 AD, she was forbidden to go to the funeral by orders of Tiberius and Livia. After the death of Livia in 29 AD, she took care of Germanicus and Agrippina the Elder's youngest children---Caligula and Drusilla.

In 31 AD she exposed a plot between her daughter Livilla and Sejanus, Tiberius's Praetorian Prefect. This led to Sejanus's downfall and to the death of Livilla. Claudius, her biggest disappointment (she once called him a "monster") was the only one of her children to survive her.

She committed suicide in 37 AD on Caligula's orders after expressing unhappiness over the murder of her youngest grandson, Tiberius Gemellus. There is a passage in Suetonius's "Life of Gaius" that mentions how Caligula may have given her poison himself.