What is the correct grammatical format for this sentence?

Everyone and his dog are getting married. Everyone is singular so requires a singular adjective (his or her). A plural subject (everyone + dog) requires a plural verb. This is correct but sounds incorrect because it's almost always said incorrectly. (On the TV show "Frasier," Frasier and his brother ALWAYS use correct English, but it often sounds wrong because we hear and read incorrect English all day, every day. Watch some re-runs to experience this.) You could say "dogs" which wouldn't change anything else in the sentence, but usually "dog" is used.