Sometimes it was the sigh at the end of a fretful night up with a feverish baby;or the opposite, the joyous cry of an exuberant 3-year-old eager to get the day going.

• 有时，它是在焦急的照顾发烧的孩子一整夜后的一声轻叹，有时则相反，是充满活力的三岁孩子渴望新一天开始时的一声欢呼。