Gee. This brings back memories as a kid watching the older kids play with strings. I still don't know how they did it. But I just love the imagery of Charlie holding the strings between his fingers and making designs and more than that, I love Don trying to pull Charlie back to reality by destroying the design. It's how I feel about Charlie, the brilliant one who lives alot in his mind, in his maths, in his theorems and probabilities and how Don, the older one, the practical one, the protective brother always bringing Charlie back to earth, back to him because he loves Charlie so much. Very lovely, lovely thoughtful, poignant fic!