"Natasha takes Mary into the room where Andrew is lying, and Mary is shocked to see her brother looking soft and gentle. Mary knows this appearance to be a sign of his approaching death."
Natasha tells Mary there has been a change recently in Andrew, and while Mary expects that means he has become soft and gentle because he is dying, she is shocked to find it is the opposite -- he has become hard and indifferent. His mind has became fixed on the next life and so he no longer has any emotions for anything in the current life.