Often parents become too involved in their kids athletics. Parents often get upset about their child's playing time -- especially at the highly competitive level or when the child is at the junior or senior level in high school or college. In my opinion, the best players should
play. Age or any other politics is irrelevant. Parents should stay out and let the coaches handle it. If a player truly believes that he or she should get more playing time or a starting position then that needs to be taken care of between the coach and the player. I don't think parents need to get involved at that stage. They are not at practice every day and they don't see everything that the other coaches and teammates see.
If the player asks the coach what they can do to improve or get more playing time and the coach replies with "nothing" or a statement explaining that they will never "move up", then you have a problem that calls for adults. The next step is to bring the parents AND the player in for a meeting with the coach. If the coach continues to be persistent and does not provide the player with any ways for improvement, then the family should go to the athletic director of the school. After that, the parents have done everything they can and should then step back and let the school handle the problem. Meanwhile, the athlete should do everything they can to get better and have a great attitude.
I know from personal experience that when you ask a coach "what do I need to do to get better?" they really appreciate it and respect you for it. Not very often does a coach reply "nothing". It is a great learning experience to be able to sit with your coach and get constructive criticism and ask for ways to improve. It will make you grow as a person and I believe it will only result in a happier relationship between coach, player, and parent.