"We is who the Earth is for?" [closed]
Solution 1:
Technically, the correct grammar would be "My daddy and I stay right here. The earth is for us" No starting a sentence with "But"; first person nominative singular following another noun for the compound subject of a sentence; plural subject matches plural verb; and no ending a sentence with a preposition,
BUT all through the movie, Hushpuppy and many other characters use a stylized regional dialect of English so the rules of grammar become moot. As @Lumberjack said, this "WE IS" formula is a very common mistake for those who speak English as a second language. There could be many reasons for this usage, but it seems the three most likely are:
- Lack of grammatical instruction
- Confusion from the interrogative form as @Jim suggested
- The speaker intuitively interprets "WE" as a collective unit. In their minds this unit is a singular entity, and so they use a singular form of the verb.
The purpose of language is communication, and closed groups tend to form their own rules of usage, grammar and syntax.
Incidentally, Winston Churchill, an excellent communicator, was once challenged by a speechwriter for finishing a sentence with a preposition. He wrote a quick note in response: "This is the kind of pedantic drivel up with which I will not put!"
Solution 2:
The usage is dialectic, and would be incorrect in standard Englishes.
The Beasts of the Southern Wild is set in an impoverished and isolated area of southern Louisiana, and filmed in Terrebonne Parish— deep in Acadiana, where many people speak Cajun English, and some still speak Cajun French. While inconsistent number agreement itself isn't distinctively Cajun, it is clear that her community is unschooled, and it is unsaid whether Hushpuppy has had any exposure to "proper" grammar.