Harry Potter And The Girl Who Lived

What would have happened if Harry hadn't been an only child? How would his story change? Colin Potter, Harry's twin, separated when their parents died they are reunited at Hogwarts. Colin is a strong, cunning person who seems to know many things beyond a simple student, but for everything Colin reveals, something is held back, How Slytherin of Colin. NOT Slash. REWRITE AT WORK!