A good memory verse for our family is 1 Cor. 13: 4 "Love is patient, love is kind".
Whenever the kids get impatient with one another (especially in sharing toys) or say something unkind to each other, I remind them of 1 Cor 13 by saying "Love is...." and they fill in the blank. It immediately causes them to stop and think and to take a minute to quickly apologize and do the right thing instead.
God's word is truly powerful and penetrates the heart (Heb. 4:12). It is awesome!