At first glance, the phrase splits into two images. The first is obvious and warm: younger sister time for harmony. It points to the uniquely calibrated space that forms when a younger sister is around — a time marked by teasing, tenderness, and a different tempo than the rest of the household. Younger siblings often set a different rhythm: they demand play, lighten moods, and ask for explanations in ways that slow adults down and make them notice the small wonders of ordinary life. Harmony here doesn’t mean perfect silence or agreement; it means a working accord where disparity and surprise contribute to balance. A family’s harmony is not a steady chord but a nimble sequence, a call-and-response that depends on voices of different ages and temperaments finding a groove.