Harry Potter: Dumbledore trusted me to see this through.
Aberforth Dumbledore: What makes you think you can trust him? What makes you think you can believe anything my brother told you? In all the time you knew him, did he ever mention my name? Did he ever mention hers?
Harry Potter: Why should he...
Aberforth Dumbledore: ...Keep secrets, you tell me?
Harry Potter: I trusted him.
Aberforth Dumbledore: That's a boy's answer. A boy who goes chasing horcruxes on the word of a man who wouldn't even tell you where to start. You're lying!