I was 9 years old, playing a game with myself, knocking the tennis ball back and forth between the court and my racket as fast as I could and for as long as I could without letting the ball escape me. When I lost the game, I’d pick up another ball and try again. I was on the sidelines, keeping myself busy as my dad continued his game of tennis with his friends. I wasn’t really sure when it started, but it became clear that something was wrong when it wasn’t going away. There was a heavy, rapid pounding against my chest. I started slowly calling out to my dad, walking over to him. He stopped his game and called out to me, asking what was the matter. Halfway to him, tears were streaming down my face. I was full of fear and I wasn’t even sure why.