As W. Labov has passed away, I came across a comment reposting this screenshotted request, along with the paper in question:
https://betsysneller.github.io/pdfs/Labov1966-Rabbit.pdf
The paper is quite a rollercoaster, ranging from describing of disturbingly racist ideas about native Hawaiian and Black children that some scientists still pushed at the time (1970!*), to Labov's own disarmingly cute and humane solution to the issue of testing children's language abilities.
Edit: *1970 - according to the article itself, which is apparently based on Labov's 1970 talk; however, the URL suggests that the article was published in 1966, which is contradictory. I'll try to find out where and when this was actually published...
Edit 2: It looks like it is from 1970, from Working Papers in Communication, vol. 1 (Honolulu: Pacific Speech Association). It is surprising that a recently published book also claims that it's from 1966, probably the authors got the file from the same URL with the wrong year.
Edit 3: The original Twitter thread: https://xcancel.com/betsysneller/status/1516848959284678656
My step brother had a somewhat similar story but in reverse. He couldn't read, though. He memorized the words of the picture books. So he could go through them all beginning to end and answer questions about the stories, but if you opened to a random page, he had no idea.
I had that same problem as a kid because my mom read to us every night and I had all the books memorized. They realized I basically couldn't read along with severe test taking anxiety, so they nearly put me in special ed in first grade. Somehow I ended up in gifted ed by second grade
That's almost exactly what happened. Except my stepbrother did it intentionally. Not that he was trying to pass a test or anything. But he would intentionally request the same books over and over until he had memorized them.