One of the three causes of sibling conflict is that children want to be first or best. In fact, they often want to exalt themselves and put others down. When a child boasts a lot, it should be a flag that this area needs some attention. Kids say things like, "I know how to do that" or "I can do that better than you." Children try to feel good about themselves by focusing on their own accomplishments.
Talk to children about how to measure their value and worth. It's not good enough to find people that you are better than. God’s solution to feeling good about who you are is to please him; and it all starts with being a humble servant. A servant attitude directly addresses the problem of boasting. A servant's reward is the statement, "Well done, good and faithful servant." Children must learn not to compete with others but to do the best job they can, comparing themselves only to themselves and the standards and goals appropriate for them.
When you hear boasting, or see a child elevating himself or herself while putting another down, take time to point out the mistake your child is making. It's best to point it out in private or at a later time by saying something like, "I have noticed something about the way you think that concerns me. It seems that you are measuring how good you are by comparing yourself to others. You seem eager to boast and point out ways you are better. I think you're going to be an unhappy person if you keep that up.
"When you see another person accomplish something good, I want you to say something nice about that person, not about yourself. Would you please think about that? If I hear you boasting, I'll try to point it out to help you see it. I'd like to help you think in more mature ways than that." After all, James 4:16 says, "As it is, you boast and brag. All such boasting is evil."
This parenting corner is adapted from Dr. Scott Turansky & Joanne Miller of the National Center for Biblical Parenting