Rosalie Potter is Harry Potter's older sister but, Harry doesn't know he has a sister because Dumbledore thought it would be best to have Harry raised at the Dursley's and he alongside the other Professors at Hogwarts would raise her because she was so powerful and was already showing signs of accidental magic and she couldn't control her powers. By the time she turned 15 she already learned everything there is to know about magic, got her license to apperate, and permission from the ministry to use magic outside of Hogwarts. When she turned 17 she realized she wanted to travel and got permission from the Professors to. What happens when Molly Weasley ask her to come visit for Christmas, so she could meet her brother, and go with the family to the quidditch world cup? And what happens when she meets a certain Weasley?