Aerea's parents were married in 41 AC. As this was an incestuous marriage, this act led to a rebellion of the Faith. When Aerea's grandfather, King Aenys I Targaryen died, it was not Aerea's father, Aenys' eldest son and heir, Prince Aegon who was crowned king, but Aerea's great-uncle (and later step-father), Prince Maegor.
Aerea's father was killed in battle in 43 AC, leading to Princess Rhaena to go into hiding with both Aerea and Rhalla. They were eventually found, however, and captured on the orders of King Maegor.
Aerea's mother, Princess Rhaena, was forced to marry King Maegor I Targaryen in 47 AC. Because Maegor had no children of his own, Aerea was named his heir, while her uncle, Prince Jaehaerys was disinherited.
After Jaehaerys claimed the throne Area was named his heir while her sister was sent to become a sister in a sept. She was a scared and shy young girl till after her uncle's coronation where she suddenly became willful and a wild terror to her tutors (it was often rumored that she switched places with her twin sister who became noticeably obedient after the coronation.)
She was eventually taken by her mother to live on Dragonstone where she was unhappy, only increasing when her aunt gave birth to an heir to the throne. She eventually ran away on the Black Dread Balerion himself, resaulting in her death a year later.