Dear Lily,
We've never met you before and dad doesn't remember you much either so all the stories we here are the ones that someone heard from this person who heard from this person, but though we don't know you because we haven't physically met, we do know what you've done for dad and for us. The love you passed to dad must have passed to us, though thankfully no one has thrown any curses at us, but maybe that's because they know what happens if you do?
We wished we had gotten the chance to say something to you in person, like good-bye or even hello, but that's okay, we talk to your portrait every day at Potter Manor and that's close enough! The only thing we want is that our words reach you, that you know that everything you've done for our family hasn't gone unappreciated now that Voldemort is gone or that you aren't remembered. Dad will always remember you and so will we even if the tales are secondhand, at least they must have a semblance of truth.
Thank you, Grandma! We love you!
Your Grandchildren: James, Albus, and Lily
fin
There was no forewarning to this stories end and I didn't even anticipate it, but I think this is a good ending to the letters to Lily, don't you think?