Vanilla is a product of Lussumo:
Documentation and Support.
I haven't read all the previous discussions so this may be a re-hash, but am I right in my perception that the 'event' occured when the Angels reached a certain age (puberty maybe) and involved the removal of adults from the scene. References to family have been limited to siblings so far and I get the impression that the residents of Whitechapel are all of an age.