From talking with some of the Linguists and Linguiphiles I work with the closest we came up with is:
"Our Father keep you safe."
nos: Us, we, our
Patre: (Pater Patris): Father
Tutus: (tutis): protected, safe, secure
Vos: you
It does seem to be a mix of maybe French and Latin...maybe a saying that was remembered and passed-down over time? Sort of an old-fashioned type of "Spanglish," ...call it "Fratin."
There's a lot of mis-remembered French in New England too...New Hampshire, Vermont and Maine especially among the second- and third-generation Americans of French-Canadian descent. You know places where family names like "Ouellette" out-number "Smith" in the phonebook, but nobody speaks French anymore.