[Kyrie is about to emphatically agree; Dante's presence in Nero's life has brought out a lot of new qualities in him that she would argue have been pretty positive. From Vergil's reaction, it seems he might not have the same view on that influence.

...and to be honest she thinks she may have an inkling of what he means, considering how formally Nero's father conducts himself. Credo hadn't been that keen on those aspects of Nero's personality either.]

Grammar?

[She frowns in surprise. What's grammar got to do with it?]

Yes, he had grammar lessons, certainly after he joined our family. My mother loved to write so she made sure we all could too. Why do you ask?