Joseph Duff was among those rescued by the fishermen, but he was later recaptured by Japanese forces and taken to Japan.
It was not until November last year that his descendants, including Olsson, learned the truth: Joseph Duff had actually survived the sinking, only to die at the age of 28 in a Japanese POW camp in March 1945.
"We didn't know what had happened to him except that we thought he had died on a ship," Olsson says.
While compiling her family tree, the 56-year-old Scottish woman conducted extensive research into her great-uncle.
But it was only at a screening of Chinese director Fang Li's documentary The Sinking of the Lisbon Maru in Edinburgh last year that she finally came to understand the full story of this little-known chapter of World War II.
"He died before I was born, but I'm his namesake," she says emotionally.
"That means my name will carry forward his name and memory."
