The profiles between your brick wall and you are unsourced. For instance, your father could use a 1940 census, his father 1910, 1920, 1930 and 1940 census. His father 1880, 1900, 1910, 1920, 1930 and 1940 census. Do that work and add the siblings and you'll be amazed at what will surface. Best of luck!