Grammar for Family Names

When I'm signing something for David and I, I write "Love, The Dietzes." I wasn't 100% sure that was correct until today!

Taken from Plural Noun Forms:

When a family name (a proper noun) is pluralized, we almost always simply add an "s." So we go to visit the Smiths, the Kennedys, the Grays, etc.When a family name ends in s, x, ch, sh, or z, however, we form the plural by added -es, as in the Marches, the Joneses, the Maddoxes, the Bushes, the Rodriguezes. Do not form a family name plural by using an apostrophe; that device is reserved for creating possessive forms.

When a proper noun ends in an "s" with a hard "z" sound, we don't add any ending to form the plural: "The Chambers are coming to dinner" (not the Chamberses); "The Hodges used to live here" (not the Hodgeses). There are exceptions even to this: we say "The Joneses are coming over," and we'd probably write "The Stevenses are coming, too." A modest proposal: women whose last names end in "s" (pronounced "z") should marry and take the names of men whose last names do not end with that sound, and eventually this problem will disappear.