I admonished, realizing this would penalize our team. I held firm, and we lost the game. But Peter's conduct improved, and his parents thanked me in the end. Rules need to be spelled out from the start, then reinforced consistently. Good sportsmanship and appropriate behavior have to be expected from players and coaches.
Enthusiasm is contagious.
Kids like coming to practice and playing games when the parents are fun to be around. Laugh with them. I look for something to praise about each child. One of my players, Derek, had little natural ability, but he was a whiz at keeping a scorebook. Derek could rattle off each player's batting average, runs scored and strikeouts.