Prudence (aka Emily Yoffe) answered my email asking if she thought the letter writer could possibly be referencing Sassafras.
She tells me that she, unfortunately, has no way of getting in touch with the people who write into the chat, so there is no way to pass on a message. So, we have to hope that the original letter writer does the right thing, and we (or a family like ours, who is missing a fuzzy member) gets a call very soon.
This, to me, underlines how much our search depends on people in our community. A child picked up a flyer and brought it to her mother's attention, the mother considered what to do and made an effort to work out her dilemma, Prudence picked the question and answered, someone was kind enough to point me to the chat, volunteers gathered possible email addresses at which to write Prudence, and Prudence wrote back. None of those people in the chain had to do anything - they gave a little time, exercised a little compassion, and helped get me to a place where I've done what I can. (Besides firmly crossing my fingers that the phone rings - but that happens every day, all day.)
Things didn't turn out the way I dreamed they would with this - and, believe me, I am always dreaming of happy endings - but I am extremely grateful to all the people who continue to show they care.
EDIT: A number of people have asked/argued that Prudence must have more information and pressed me to get back in touch with her or allow them to get in touch with her. Her answer was clear - there is no more information that she can give to us. Please do not bombard her with messages. She was kind enough to get back to me, and I appreciate that. If you read her regularly, then you know she loves dogs, and would be just the kind of person who would help if she could. Unfortunately, she can't.
You don't have to ruin the relationship with the neighbor. You just have to call the number on the flyer, give your neighbor's address, and say she recently adopted a dog that looks remarkably like theirs. You must know what your neighbor's new dog looks like because she's been out and about with it, which means anyone in the neighborhood could have noticed. If the neighbor is contacted by the peopel with the miss dog, then comes to you with accusations, just say you don't want to get in the middle of a dispute she may be having with the owner of the lost dog.