Julia the Elder
Julia the Elder (39 B.C. to 14 A.D.) was the only biological child of the first emperor of Rome, Augustus. Born at the same time Augustus was leaving her mother and marrying Livia. Julia first married in 25 B.C. to her cousin Marcellus, 14 being a common age of marriage among Roman girls in that time period (or in some cases even younger). Marcellus was popular in Rome, but he met an early death in 23 B.C. With Augustus' childhood friend Marcus Agrippa coming back into the Emperor's good graces at that time, he and Julia were married in 21 B.C. They had many children, including three sons before Marcus also died in 12 B.C.
Julia married Tiberius in 11 B.C., but within a few years the marriage had soured if it had ever worked out at all and they lived separate lives. They had no children. In 2 B.C. Julia was charged with adultery and apparently had had multiple lovers who were either sent into exile or took their own lives. Julia herself was sent into exile. With the death of her father in 14 A.D. and having already seen her three sons die prematurely, she either starved herself or was helped to death by the new Emperor, her former husband Tiberius. It is believed her mother-in-law Livia had a hand in helping to see that the male bloodline of Augustus passed away so that her son Tiberius would rule after Augustus.
Julia eventually did have a descendent serve as Emperor. Her daughter Agrippina married Germanicus and their son Caligula came to be Emperor in 37 A.D., although, he was hardly a bright spot in Roman history.