On the train to Hogwarts in the first book, Ron says he uses Charlie's old wand. I have two questions:
Doesn't he have to kill or disarm Charlie to be able to effectively use Charlie's wand? How could he do this with no wand.
Didn't the Weasleys just have to buy Charlie a new wand anyway? Why didn't they buy Ron one? Charlie would be fine with his old wand, unless he drove a car into the Whomping Willow.
Here is what Ollivander says:
"Much also depends on the wand itself. In general, however, where a wand has been won, its allegiance will change." ".....the conquered wand will usually bend its will to its new master."