"I just do," Harry cut across her, deciding not to bother and explain how a Pensieve worked. A beat, and then.... he thought better of it. "There's a.... magical bowl that can allow you to see into someone else's memories." He was almost amused at the wonder he saw gathering behind his aunt's eyes, and it compelled him to continue extending this olive branch of sorts. "I know about you, and Snape and my mother."