A noble goal to compile such a list.
It did seem to me with respect to your query "I have been wondering...why we do not know Humbert's birthday (in contrast to Fyodor G-Ch's, his father's, Sebastian Knight's, Pnin's, and John Shade & co's) that the list of characters for whom we know birthdays
is a list of good guys, exclusively.
> Date: Tue, 23 Apr 2013 21:21:13 -0400
> From:
nabokv-l@UTK.EDU
> Subject: [NABOKV-L] Birthday Wish
> To:
NABOKV-L@LISTSERV.UCSB.EDU
>
> I had a wish for VN's birthday, which was to compile a list of the
> birthdays of his characters, and also a list of major characters for
> whom we do not (seem to) know the birthdays. My wish, however, did not
> come true! Still, I have been wondering for most of the past year why we
> do not know Humbert's birthday (in contrast to Fyodor G-Ch's, his
> father's, Sebastian Knight's, Pnin's, and John Shade & co's). HH does
> mention the general concept of his birthday twice ("...before my
> thirteenth birthday"; "after my sixteenth birthday"), and the 12th,
> 13th, 14th, and 15th birthdays of Dolores Haze.
>
> Cheers to VN at 114!
>
> Steve Blackwell
>
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