One of the greatest verses to memorize concerning sibling rivalry is the good old Golden Rule: "Love the Lord your God with all your heart and with all your soul and with all your strength and with all your mind'; and 'Love your neighbor as yourself" (Luke 10:27).
These are some positive rules you may use at your home, and remind your children when they have playmates over:
1. Love God-Don't hurt God.
2. Love others-Don't hurt others. (And don't hurt things that belong to others.)