Search the Washington Post's Archive. The link is:http://pqasb.pqarchiver.com/washingtonpost/search.html?nav=l...
I did an advanced search (on the right side of the screen for the period 1877-1986) for Fannie Brown between the dates of 4/1 and 4/30/1966 and there were two results - one on the 23rd, the other on the 30th. Both are listed as obituaries. Next to each item you can preview or buy the article. There was nothing of the article to preview, except it indicated the section, page# and wordcount of the article.
You can check your local library and see if they have access to this online archive (through ProQuest), or, you can go ahead and buy the article(s) online, but you will need to create an account with them (so that articles you purchase will be charged against a credit card). If an article isn't what you are looking for, you can request a refund.
Hope this helps.