The Grandma of Lucius Antonius was the elder sister of which Emperor ?
Lucius Antonius (grandson of Mark Antony):  He was the grandson of triumvir Mark Antony and Octavia (sister of Augustus). Octavia the Younger: Octavia the Younger (69 BC – 11 BC), also known as Octavia Minor or simply Octavia, was the elder sister of the first Roman Emperor, Augustus (known also as Octavian), the half-sister of Octavia the Elder, and the fourth wife of Mark Antony.
Augustus