Celebrim
Legend
Probably the same exactly the same down to my preference for trying to give characters distinctive voices and mannerisms, but since this is a situation where the player cannot get immediate feedback as to how well they are performing, I would have rolled the perception checks by the player. Thus, there would be no relief to the players suspicions had they rolled particularly well. All the player would know is that they aren't detecting anything unusual. Whether being paranoid around 'granny' mildly offends her, mildly amuses her, or earns some level of respect would depend on the personality I'd given the character, but would collectively along with the rest of the RP in the scene go to deciding the difficulty of any initial reaction check to see if 'granny' likes the character.