Question: are there 3 clegane brothers?
Answer: The former head of the family was Ser Gregor Clegane, known as "The Mountain That Rides," who has since been named to the Kingsguard. Gregor's younger brother, Sandor Clegane, known as "The Hound," was the rightful lord of House Clegane. The Clegane sigil is three black dogs on a dark yellow background.