Daenerys Targaryen (daughter of Aegon IV)

Daenerys Targaryen is an unseen character in Game of Thrones. She is not expected to appear in the series, being long dead by the time it begins. Daenerys was a Princess of the Targaryen dynasty and the namesake of Daenerys Targaryen.

Background
Daenerys was the daughter of King Aegon IV Targaryen and Queen Naerys Targaryen, born on the year 182 after Aegon's Landing. She was the sister of King Daeron II Targaryen. He also had a half-brother, Daemon Blackfyre, born of the affair between his father and Queen Daena Targaryen, the sister-wife of Baelor I Targaryen. She married the Prince of Dorne, Maron of House Martell.

Season 1
Daenerys, along with her family, is mentioned in the House Targaryen's entry of the book The Lineage and Histories of the Great Houses of the Seven Kingdoms.

In the books
In the A Song of Ice and Fire novels, Princess DaenerysDaenerys was born well after her older brother, Daeron II, to the point that Daeron had already married and had a son, Baelor Breakspear. Her betrothal to the Prince of Dorne, Maron Martell, was brokered by her brother Daeron as part of the treaty bringing Dorne under the authority of the Iron Throne. Daenerys supposedly loved her bastard half-brother, Daemon Blackfyre. It was said the main reason Daemon rose in rebellion against Daeron was that Daenerys was denied to him. A year after the rebellion concluded, in 197 AL, the marriage between Daenerys and Maron was carried out and Dorne formally joined to the rest of the Seven Kingdoms.

After Daemon's death, Prince Maron built his new bride the Water Gardens, a place of beauty made of colored marble with pools and trees. Her children played in the pools along with the children of other highborn lords. One day when the sun was hot, she took pity on the children of the servants and guards and allowed them to play in the pools with the highborn children, starting a tradition that is still kept in Dorne to this day.