Letters to Harry Styles

Sydney Carter was adopted at age 15 and it wasn't the best thing that happened to her. She gets beat by her step dad, she barely gets fed and she found out a month ago that she's pregnant at age 17 by her boyfriend who left her when she told him. Sydney finds a letter in a box in her basement that was sent to her but she never actually got it. Her step dad must have hid it from her. What happens when she starts writing to this mysterious person? Will her life get better? Or worse?