Appropriately set in Providence, RI as that was the home of H.P. Lovecraft who wrote the story "The Rats in the Walls" which apparently inspired this film. Though the short story was set in England not Rhode Island.
In the original Don't Be Afraid of the Dark (1973), Sally was Alex's wife, not daughter, while in this version a woman named Kim is his wife. In the original Sally, Alex's wife, was played by an actress named Kim - Kim Darby.
There are two early hints of the fairy connection. When Sally finds the secret garden, she walks through a circle of mushrooms- - a fairy ring. Also, the housekeeper's name is Mrs. Underhill. Underhill is one of the names of where fairy folk come from.