The song shows the moral responsibility of a mother who teaches the lesson of responsibility and taking care of one’s belongings to her kittens.For her, giving a reward is an easy way won't make her kittens responsible for their things. This is the reason she deprived them of pie and told them to work hard and then receive a pie.Thus, the song expresses a change in emotions from sadness to happiness, from being deprived of the pie (a reward) to receiving a reward.