Dear Teddy,
I have written this letter in case I don't survive the battle. The world today as I know it is bleak, sad and everybody lives in terror. If you receive this, it will be your 17th birthday, and as I won't be here to give you something special. This is the best I can do.
I have left you in your mother's care; yet I suspect she will follow me as she feels the same way as I do about staying behind. Many people will think my decision is selfish; fighting a battle that is heavily against our favour- and as a result leaving my son an orphan. However, there is a side that not many people will understand. Currently, the whole of the wizarding world has gone into hiding- most of the shops have been boarded up, turning the usually warm and welcoming mood of Diagon Alley into a frigid and frightening one. Imagine a world where you can trust no one, where everyday you wake up and hope that you and those you care for will still be alive to see the sunset. The collapse of the world you know and love is out of your control.
The last time this happened, two of my best friends died and there was nothing I could have done to prevent it. These two friends gave up their lives and saved the world from the terror we were living in. If it meant that my presence in the battle could kill at least one Death Eater, and save at least one person from the harm that they cause, my death would be worth it. If no one turned up to help because they assumed the chances of our success were too low, then of course we would have lost. But with hope alone we can stand together and maybe we can save the lives of many. War will always be messy, but everyone is fighting for someone else's future and for me; the only future that matters is yours.
You may think that my decision was the wrong one, but everything that I do is designed to make your future a better place. What if the Death Eater that I kill is the one that was destined to hurt you? Now, how would my death be in vain?
I'm sorry that you won't get this letter until you're 17, but now I can be sure that you are old enough to understand my point of view, and comprehend what was running through my head the day I abandoned you to fight in the war.
I love you even if I'm not there,
Remus