Its been done before but here is my take.

The Potter's had two children before they died. Twins to be exact. Harry had a sister named Chloe, aka Clover (she loves clovers). And together the were the chosen ones and Potter twins. They both had their fathers black hair and their mothers green eyes. Harry was only about an inch taller and considered himself the older brother, as he was born two minutes before Clover. Clover had her mothers build while Harry had his fathers. Both had their dad's love for trouble and pranks and his charm (in Harry's case) and their mom's kindness. Not to mention their moms temper and both of their parents protectiveness. But when Lily and James died the twins went to the Dursleys. They both were beaten, locked in a small cupboard, placed with endless chores, and possibly worst of all raped. They hate their lives. That was until they were 11.

I know its short but it wasn't even a real chapter.