A Little Mother to the Others by L.T. Meade

That night the children's young mother went on her journey. The summons for her to go came unexpectedly, as it often does in the end. She had not even time to say good-by to the children, nor to her husband, only just a brief moment to look, with startled eyes, at the wonderful face of the angel who had come to fetch her, and then with a smile of bliss to let him clasp her in his arms and feel his strong wings round her, and then she was away, beyond the lovely house and the beautiful garden, and the children sleeping quietly in their beds, and the husband who was slumbering by her side -- beyond the tall trees and the peaks of the highest mountains, beyond the stars themselves, until finally she entered the portals of a home that is everlasting, and found herself in a land where the flowers do not fade.

In the morning the children were told that their mother was dead. They all cried, and everyone thought it dreadfully sad, except Iris, who knew better. It was Fortune who brought in the news to the children -- they had just gone into the day-nursery at the time.