Ser Cedric Costayne is the heir to the Three Towers, and a knight who squired for the Hedge Knight Ser Roland Bridgewater. Upon being knighted he was dubbed 'Ser Cedric of the Cells' by his mentor due to the knighting ceremony being in a makeshift prison.
Cedric was born an only child in the year 487 AC to Gregor Costanye, and spent the entirety of his childhood at their ancestral seat of the Three Towers. As the heir, Cedric was trained by the master-of-arms with both sword and lance, and taught the basics of court and literature which will be needed when he becomes the Lord of his house. He visited Highgarden with his father on several occasions as a child and has fond memories of the city. He dreamed of becoming a knight during his childhood but his father denied him the request of becoming a lord's squire on several occasions, leading to tension between the father and son.
Due to unknown reasons, Cedric left Three Towers at the onset of the War Of The False King. During his travels he met the hedge knight Ser Roland Bridgewater and fulfilled his dream of squiring for a knight.
During this period, Ser Roland disappeared and Cedric began tracking who he believed to be his captors to King's Landing. While Searching for his master in Flea Bottom, Cedric was mugged and left seriously wounded in the streets. He was rescued by a daughter of a local tanner, called Mira. She helped heal his wounds while he set up a small information network through King's Landing in order to find his mentor. A piece of information led him to a bandit camp where he found Ser Roland. Before granting the Maimed Knight the gift of mercy, he knighted Cedric, dubbing him 'Ser Cedric of the Cells' due to them being in a makeshift prison. He fled the camp, setting out to eventually kill the bandit leader, an unnamed member of house Kidwell.
"You're brave, boy" He said Fiercely. "You're skilled and loyal to a fault" His eyes darkened then "But you're too rash, foolish and naive, you can't take them all on."- Ser Roland Bridgewater
"You have it in you to be a great knight, just don't let your hotheadedness lead you astray."- Ser Roland Bridgewater
Gregor Costayne (unknown status)
Lymond Costayne, Half-brother
Ben Costayne, Uncle
Petyr Costayne, Uncle