I saw Grappelli, age 80, in 1988, and he was as wonderful as ever on violin and piano. I have often wondered why his name was spelled "Grappelly" on the earlier works, and later, "Grappelli." On this page (by Jim Moss), I found:
What is interesting is the spelling of his name, Grappelli or Grappelly. If you look on the old Django records you see Grappelly yet if you look at later solo projects you see Grappelli. I asked once why the two different spellings of his name, to which he said it was Italian and French. That is what he said and I didn't push it.