Dear Rea,
I'm unbelievably excited to start Hogwarts tomorrow. I can't wait to see what house I'm in! I hope it'll be Ravenclaw, like you. All those years in advanced classes ought to pay off somehow.
But, you know, I must say: while I'm excited, I'm also horribly sad that I don't have you with me for my first day of school. It can never be how I always imagined, but there's no possible way I'll spend my whole time at Hogwarts without you. I'll find you, Rea. I won't stop till I do or I'm dead. Though I hope it doesn't come down to the latter.
I'll be sure to write you about my first day. I can't wait to see Rowan again. Hopefully, I'll meet some other friends too! When I do, I can't wait for you to meet them, too.
See you soon,
Attie