My 5 year old (nearly 6) is, frankly, naughty. He’s clever, charming, thoughtful and gorgeous but also just enjoys mischief. He’s mean to his brother (tripping him over, calling him names) and sometimes rude to adults. He is very unreliable when it comes to following instructions and often just defiant. He breaks things through carelessness. I try removing him, distracting him, consequences but basically that has very little effect. Is this just 5 year old behaviour that I need to ride out or am I doing something terribly wrong?