That makes sense for people, I think (although I recently read a novel in which a Mr and Mrs Wolf were referred to jocularly by the main character as "the Wolves"), but I'm still not sure about months.
That probably is the least wrong option, though. Thanks milos.
Julys. It only looks funny because we aren't used to seeing -ys. But it's one of our grammatical necessities because (to me at least) it is improper to change about a proper name when pluralizing in English.
One week from now I will be visiting my friend D. McKelvy, and his family, the McKelvys. They are not McKelvies. Nor are they McKelvy's, despite the wanton deviance to this construction by those who abhor virtue. One of them is a McKelvy, and two are McKelvys. Same for July and Julys.