Rosabella hope Johnson (black) was raised my muggles, but is a pureblood her mother Rebekah Maximoff, and father Sirius Black. Rosabella lived on number 3 privet drive next to the Dursley's. She first meet harry in kindergarten they became close even though they never saw each other outside of school- hell did she know they lived next door. (I'm going to start with them as little kids and then jump right into 3rd year for obvious reasons and then continue the story. And also shes not only a maximoff witch she also has a special ability...)