“I suggest that we go back to your house, to see whether your sister has returned. May I ask whether, when you last spoke to her, she gave you to understand that she meant to stay with Mrs. Ilam?”
Pauline breathed a reluctant affirmative.
“No hint that she was going out?”
“None. And——”
“And what?”
“Oh, dear!” Pauline sighed. “Must I tell you? Yes, I must! I’m sure Rosie is acting for the best, but really it was not her turn to watch Mrs. Ilam to-night.”
“Whose turn was it?”
“The nurse’s.”
“And your sister changed the rotation?”
“Yes. She said the nurse needed a holiday, and told her she could go away for twenty-four hours, and that she would take her place.”