Silas was born and raised in Aphrodite City on Venus to Bruce Grayson and an unknown woman. He was always used to being the center of attention and a joker, until he until he discovered he was a metahuman when he defended himself after he was jumped by bullies in his high school. He inherited psychic abilites, apprently from his mother, most prevalent, the ability to create fire with his mind, as well as telekinesis, though he can only internalize it to make himself fly. Soon after, he immediately went under the tutelage of his father, Bruce, who was tought by his father, Dick Grayson martial arts as well as the finer points of criminology.
Not long after completing this training, Si accidentally used his powers to stop a bank robbery. Being seen by a mysterious man, he was told to follow him. Si agreed to follow him. He first asked him his name. He told him Silas Grayson. He then asked, "Any relation to Dick Grayson?" He told him that that was his grandfather. The man's jaw dropped and he told him he had to come with him to Mars. Si reluctantly agreed and followed the man to Mars to Batman Inc. Headquarters. Then once he showed The leader his powers and fighting skills, he was welcomed into Batman Inc. under the codename Firebyrd.