When I was a first-year student, I could have written something very similar. In fact, I wrote lots of letters all throughout my life. Not just to my mother but to people that I missed. (You’ll find them in Letters).
So, it hurts, to think about my mother. And to Delphi, I know you probably wanted to write to your mother a lot more than we did.

Mum,

To the best and most brilliant mother that I ever had. There are no words to tell you how much I love you and how much I miss you. I have and will always be strong for you, brave for you and kind for you. I will never be the best but I will try for you. I would have you back in a heartbeat but I know what is right and what is wrong. I miss you, I miss Uncle Severus. I miss what I can tell you. I wish I could tell you what I have done, show you my children and tell you I am happy. I MISS MY MUM. I miss you.

Lou.