How did you decide that Molly Weasley would be the one to finish off Bellatrix?
"I always knew Molly was going to finish her off. I think there was some speculation that Neville would do it, because Neville obviously has a particular reason to hate Bellatrix. ..So there were lots of options for Belatrix, but I never deviated. I wanted it to be Molly, and I wanted it to be Molly for two reasons. The first reason was I always saw Molly as a very good witch but someone whose light is necessarily hidden under a bushel, because she isn't in the kitchen a lot and she has had to raise, among others, and George which is like, enough... I wanted Molly to have her moment and to show that because a woman had dedicated herself to her family does not mean that she doesn't have a lot of other talents." -JK Rowling