When, later, I was able to ask Natalia Savishna about Mamma's last
moments she told me the following:

"After you were taken out of the room, my beloved one struggled for a
long time, as though some one were trying to strangle her. Then at last
she laid her head back upon the pillow, and slept softly, peacefully,
like an angel from Heaven. I went away for a moment to see about her
medicine, and just as I entered the room again my darling was throwing
the bedclothes from off her and calling for your Papa. He stooped over
her, but strength failed her to say what she wanted to. All she could
do was to open her lips and gasp, 'My God, my God! The children, the
children!' I would have run to fetch you, but Ivan Vassilitch stopped
me, saying that it would only excite her--it were best not to do so.
Then suddenly she stretched her arms out and dropped them again. What
she meant by that gesture the good God alone knows, but I think that in
it she was blessing you--you the children whom she could not see. God
did not grant her to see her little ones before her death. Then she
raised herself up--did my love, my darling--yes, just so with her hands,
and exclaimed in a voice which I cannot bear to remember, 'Mother of
God, never forsake them!'"

"Then the pain mounted to her heart, and from her eyes it as, plain that
she suffered terribly, my poor one! She sank back upon the pillows, tore
the bedclothes with her teeth, and wept--wept--"

"Yes and what then?" I asked but Natalia Savishna could say no more. She
turned away and cried bitterly.

Mamma had expired in terrible agonies.