You said -
I know you can do it. You've always been the smarter one of us.
I never thought of it that way. I have been around long enough and seen enough of the depth and breadth of intelligence to be aware that I am not really that smart; I'm sure you know it too, but that never changed the way you thought of me.
I marvel at how much confidence you have in me, and how much you believe in my abilities and determination. You never once stop believing in me even when I have stopped believing in myself. You are sure I have the strength to overcome all challenges and adversity even when I feel I am all drained-out. You are constant and unwavering in your love and support for me. You have always stood by me despite my eccentricity, excessive use of sarcasm and inclination to give in to the horrifying temper I never seem to be able to completely rid myself of.
I realise how lucky I am, and I am grateful I had you in my life all these years. I am doubly grateful knowing I will still, and always have you with me hereafter.
You'll have me too. Oh, and I'm sorry about the time I rode so closely to the row of parked cars, and caused your knees to knock into one of them which caused you to fall off my bicycle onto the road...