(CNN)-- The children know the man whose portrait hangs above their playroom door as Mister S or Mister Somerton.
His real name remains a mystery more than 70 years after he was found dead in a smart brown suit on an Australian beach, a half-smoked cigarette resting on his collar.
The kids assume he's a distant relative, but he could just be a stranger whose story has fascinated their father for more than a decade.
University of Adelaide professor Derek Abbott first heard about the Somerton man in 1995, and has spent several years campaigning for his body to be exhumed so scientists can analyze his DNA to determine his identity.
