A team can't win a championship if they don't win the semifinal. There's nothing worse than looking at your fresh and rested pitchers in the parking lot as you head home.
You've already had your turn to play the game. Now it's your son's game. Cheer him on. Support him. Help him improve. But don't get overly emotionally wrapped up in it. It's only a game. It's HIS game.
Here's my best advice to parents of young players new to the game. Win or lose the kids will usually come away from the field thinking they had a good time. Having a good time is the #1 goal of playing. Any negatives are gone by the time they hit the concession stand. The only time they determine they had a bad time is when disgruntled parents tell them there's a problem (real or imagined).