Premise: Often Mrs. Jo hushed them all , saying , with a sob in her throat , `` The noise may frighten them , let me call ; Robby will know my voice ; '' and then she would cry out the beloved little name in every tone of tenderness , till the very echoes whispered it softly , and the winds seemed to waft it willingly ; but still no answer came .
Hypothesis: Robby would not know her voice.