Вероятно, оно так отчасти и было; по письму видно: мамаше он показался резок, немножко, а наивная мамаша и полезла к Дуне с своими замечаниями.
Most likely it was partly like that, from mother's letter it's evident: he struck her as rude a little, and mother in her simplicity took her observations to Dounia.