Okay, time's up.  The word -- which dreadbeard got before finishing the description, a claim I have no reason to doubt -- is BETRAYAL, which is perhaps the point of the little story; maybe Milne had good reason, as perhaps Victoria did, not to discover it.  I admit that I went wrong for a while trying to come up with a word with ALBERT in it, which certainly is in BETRAYAL though not in the right order, and would have given Vickie further pause.  It was anselmo_b 's hint of "quisling" that made the word instantly pop out.  I could have got out the Scrabble tiles and done it faster, or the online scrabble tiles even.  But that would have been cheating.  Instead I just failed.