Probably read this in the early 1970s Two children, boy and girl, are turned into buttons by a woman (witch?). As buttons, they looked like carved bone and I think they were dressed as Pilgrims. They had to escape before they were sewn onto anything, because once they were sewn on, the change was permanent.
Stump the Bookseller
New format, same book stumper solving.
Perhaps The Witch’s Buttons, by Ruth Chew?
Seconded!
THAT’S IT! You guys are awesome, I had searched for this periodically over the years and never found it, and here within a few days. Thank you!!!