Plot Details/Summary
I only remember a few bits about this tale, but what I do remember is hopefully specific enough to identify it.
The story is set in modern times (20th century). A young boy digs up an old grave rumored to be the burial place of a creature known in local lore as a "Wendigo." I remember thinking this odd, because I had always heard the Algonquin myth of a Wendigo involved humans who had resorted to cannibalism. It struck me as even odder when it became clear in the story the creature was revealed to be closer to a vampire than anything else.
I do not recall what led the boy to dig up the grave, though I think it was primarily curiosity. He does so fairly late in the story, as the resolution to the tale is not long in the coming. He takes it back to his home and places it in the cellar.
That night, he hears a noise and goes downstairs with a flashlight to investigate. There is a chilling line about hearing a slurping noise and seeing the body of his pet dog on the floor, apparently drained of blood. The story closes with the boy dropping the flashlight, and seeing the light briefly catch on the face of the fanged Wendigo, who is now about to feed on the boy.
Timeframe/Publication Details
The story comes from an anthology that was published no later than the late 1970s. I'm sure of the era because I actually read the story for a elementary school book report in the late 1970s (Why yes, my selection was a fair bit darker than anyone else's)