Character's involved: Hermione, Harry plus a little bit of Ron
Plot line: After the war ends, Ms. McGonagall calls Harry, Ron, and Hermione into her office. Not knowing what to expect, the three show up at her office and discover that Dumbledore instead wants to speak with them. Dumbledore tells the trio that Harry has a sister. Dumbledore tells them that he feared harm would come to the twins, so the minute Lilly gave birth to harry, he froze everyone, and performed memory charms before handing Hermione over to the people she then thought were her parents. God, horrible at this summery/telling people the plot line thing. Sorry!
Other details: Not sure if this will be a short drabble or whatever. I don't do angst, and this little idea just wouldn't leave me alone!