Readers didn't know that Dumbledore possessed the Elder Wand until the end of "Deathly ... not only did Harry not disarm Draco via magic spell — he just grabs it out of his hands — but the ...
In his last scene with Dumbledore's portrait, 30 Harry truly arrives at adulthood. Harry knows what to do with the Deathly Hallows. He has learned to be wary of the power of the Elder Wand.