This is not my direct line, but my mother's 1st cousin is 90 and a descendant. I send him whatever I dig up.
I have a Ferdinand H. Japs marrying Dena Anna Landwehr. I have no information on Ferdinand, but did find Dena in the 1920 census in California with her daughter Loretta.
Ferdinand and Dena had 4 children, Bernard Wheaton (1882-1944), Loretta (1896-1971), Claire (1890- ) and Laura (1896- ).
If you have further information regarding this family, I would appreciate receiving it.