Ida,

I also found a WWI entry for John Henry.

John Henry
b. December 25, 1878
Residence: 228 West 61st Street, Manhattan, NY
Nearest Relative: Miss Rebecca Henry (sister)
Address:[Can't make out the City], South Carolina

The 1920 census has the family living on West 62nd Street, Manhattan, NY.

Could this be William's dad?

FYI: Found an old address
William Henry
b. 24 August 1918
486 Gates Avenue
Brooklyn, NY 11216-1578

I have seen his name as William I. Henry, do you know what his middle initial stood for?