Daeron I Targaryen, The Young Dragon, The Boy King by Amok. "'Daeren Targaryen was only fourteen when he conquered Dorne,' Jon said. The Young Dragon was one of his heroes. 'A conquest that lasted a summer. Your Boy King lost ten thousand men taking the place, and another fifty trying to hold it. Someone should have told him that war isn’t a game. Also, Daeren Targaryen was only eighteen when he died. Or have you forgotten that part?'"
King Daeron I, known as the Young Dragon, was the eldest son of Aegon III and the eighth Targaryen king to sit the Iron Throne from 157-161AC. He ascended to the throne at the age of fourteen and is famous for conquering Dorne, which he wrote about in his Conquest of Dorne.
Daenys Targaryen, also known as Daenys the Dreamer, was the daughter of Lord Aenar Targaryen. She was born in Valyria and had prophetic dreams (like Prince Daeron Targaryen and Daemon II Blackfyre). She saw the Doom of Valyria and warned her father, who relocated his family to Dragonstone, despite the jokes from the other lords. That's why the Targaryens are the only family of dragonlords that survived the cataclysm.
Blackfyre, one of two ancestral Valyrian steel longswords of House Targaryen, brought to Westeros by Aegon I. Blackfyre was passed from Targaryen king to king, until Aegon the Unworthy bestowed it on his bastard son Daemon instead of his legitimate son, Daeron, After the Daemon's death, his half brother Bittersteel took Blackfyre with him in exile to the Free Cities, where he and Daemon's surviving kin founded the mercenary force, the Golden Company. The sword's current whereabouts are…
Princess Elaena Targaryen was the fifth and youngest child of Aegon III and Daenaera. Locked away along with her two sisters. Was married for three times (to Ossifer Plum, Ronnel Penrose and Michael Manwoody) and had a total of seven children, five by two of her husbands and two born out of wedlock (fathered by her cousin and lover Alyn Velaryon).
Daeron II the Good was the twelfth King of the Seven Kingdoms from House Targaryen. His bastard half-brother, Daemon Blackfyre, challenged his rule and the result was a terrible civil war, the Blackfyre Rebellion. The war was mostly won by his sons and his other half-brother, Brynden Rivers. Daeron died during the Great Spring Sickness in 209 AC.
Baelor I Targaryen (143AC - 171AC), Successor of Daeron I and King of the Seven Kingdoms (161AC - 171AC). Brother of Daeron I and son of Aegon III and Daenaera Velaryon; Known as "Baelor the Blessed". The "most beloved" of the Targaryen kings, Baelor was also a septon and had his sisters imprisoned in the Maidenvault so they could not tempt him with carnal thoughts. Baelor made peace with Dorne following his brother's conquest.