David, you’re missed by everyone you know. Mother asks about you often but we can only tell her you’re on a long business trip. It is at least half true. As you’re looking down from above, you should know that you did not die in vain. As I analyzed every aspect of your life that I know about, the discoveries I made helped me in averting another disaster. For that I thank you! It was most regrettable I couldn’t do the same for you. Rest in peace, my little brother! Thank you for enriching our lives with yours. When my work here on earth is done, we’ll meet again. Then I can call you by your Chinese name again like when you were little. With love, your brother.

Looking like an engineer in this picture.

Taken while attending Cooper Union. Lots of hair.

Love that smile.

David was just the cutest baby anyone has ever seen when he was born.