From Tony Curtis & Peter Golenbock, "American Prince" (N.Y.: Three
Rivers, 2008), p. 135 (i.e., the horse's mouth):

"'Son of Ali Baba' was the movie where I gave a line that people
unjustly made fun of for years afterward. There's a scene where I'm on
horseback and Piper [Laurie] is sitting next to me, and I say to her,
'Yonder in the valley of the sun is my father's castle.' After the
film came out, Debbie Reynolds...went on television and said, 'Did you
see the new guy in the movies? They call him Tony Curtis, but that's
not his real name. In the new movie he's git a hilarious line where he
says, 'Yonder lies the castle of my FODDA.'"

"...Unfortunately, her version stuck with the public, and for a while
it became popular for people to quote the incorrect line in a
ridiculous New York accent."