First of all, Hads, I am writing this letter to you because I love you and want to see you succeed in your life both inside and outside of your soccer career. The most important thing about being a good player is having fun while you play. Being able to do something with your friends every day is a privilege you don't want to take for granted. Whether it's going to practice with a smile on your face, or messing around with friends during warmups, the experience is one you will never want to forget.
Along with having fun, of course, is working hard, and soccer allows you to do so in a competitive and addictive way. I know you love to win, and I know you love to run, so in order to succeed at both of those things, you have to practice a lot! Everyone has lazy days where they don't want to go to practice or when they are there, just slack off. However, making yourself as focused and productive as possible on these days are what can separate you as a player from the rest.
When I was younger, sometimes I hated going to practice. But I made sure that I went anyway, and I always tried 100% when I did.
Anyways, I just want you to know you have impacted my life a lot and mean a lot to me :) make sure you always follow your dreams, Hadley!