He knows that tone and recognizes that it's not directed at him. He only worries for what it might lead to and answers quickly rather than let the king worry that it may be something worse than what it is.

"My sight has been dulled. Where once I could see leagues, now my eyes can see no better than that of a Man."

At least his skill with blade and bow hasn't been affected. With Thranduil here, he didn't want his skills to be in any way compromised. Which means he'll be practicing more than he has been. Regrettably, it hasn't been as much as it should have been.

Nodding, he begins to lead the way along the familiar halls. What noise came from the stones is more of less ignored by the son, he's not interested in the stories of the castle unless from those he trusts.