János was born on May 29th, 1901. János' father was János Körtvélyesi and his mother was Mária Szögi. His paternal grandparents were József Körtvélyesi and Anna Tóth. He had a brother and a sister, named János and Mária. He was the youngest of the three children. He had a half-sister named Ilona. He died at the age of 78 in 1979.1