Disclaimer: I don't own! The second paragraph of Dumbledore's letter is directly from the book, but worded differently (it'd be from Lily's point of view).
Author's Note: This isn't canon, but I also know that it shall be a little out of character.
Dear Lily,
You put your trust in the wrong person and have now left Harry parent less, but why I say this is not to belittle you for that is not my intent. The reason I'm saying this is because in dying for Harry, you have given him a protection.
You died to save him. If there is one thing Voldemort cannot understand, it is love. He didn't realize that love as powerful as yours for your son leaves its own mark. Not a scar, no visible sign ... for him to be loved so deeply, even though you are gone, will give him some protection forever…
So I hope that you will forgive me in placing him with his relatives, he shall be safe there.
Albus Dumbledore
The time periods for all of these will be random, by the way.
Also, some of these are hurt/comfort and others will be humor. They are letters from people of the 'wizardry' world so most will be random and others meaningful and heartfelt.