This is a transcript of an actual letter of apology written under duress, as a condition of not being grounded for the rest of his life.
The names have been altered to protect the not so innocent.
I am terribly sorry for choking you.
I couldn't control my anger.
You are my nicest brother.
I shouldn't have done that to you.
I WILL NOT do it again. Sorry again.
Hogwart's Head Master