Sirius was born at the side of Cambridge. His father William Moffew after studies worked at Department of Magical Transportation in the Ministry of Magic for a few years, but soon left that job because of too much responsibility and started work as a shop assistant at potions shop in the Diagon Alley. There is lower wage, but William belongs to the old rich wizard family and never think about money. Although Sirius's mother, Mary Moffew is a half-blood from a poor Scotland village, and as she knows what is it to be poor, she finished  Hogwarts with quite high marks, and now makes calculations for the Gringotts Bank.  So, as you may notice, Sirius's parents have some differences, but they both love their sun as much as possible, that's why child has been growing up as a kind, hard-working, responsible and clever  boy.  Now Sirius is extremely bored with everything around him, and really exited to go to the Hogwarts and study magic. His largest dream is to become a powerful wizard, at least like Albus Dambledore. Earlier, he picked up some sticks and tree's branches, which reminded magic wands and tried to do some spells whispering random weird words. But nothing happened, and Sirius even started thinking that he is a Squib, until one accidentally.  The boy was playing with others in a tall tree, and on the high of 10 meters Sirius stood on a dry old branch, broke it and the branch fell down. But not a boy. He softly grounded like he was a feather. After that, Sirius was confident about his magic skills existing. On the other side Sirius is small, weak and thin boy, with white like paper skin. That could be a reason of  his shy, especially when boy meets some pretty girl...