Blade is 8 1/4", total length of the knife 13". If father made the knife it is probably a ww1 weapon. I think the blade looks more like ww2 design. Higman Theater Fighting Knife Dagger. Kansas City Kansas" is in sale since Saturday, July 4, 2020.
This item is in the category "Collectibles\Militaria\WW II (1939-45)\Original Period Items\United States\Edged Weapons". The seller is "classic_jewelry" and is located in Sedalia, Missouri. This item can be shipped to United States.