At some point, the sheriff tells Jessabelle that the DNA of the baby skeleton found in the grave shows that the baby was black. There are no markers for race, of any kind, in DNA.
When Jessie and Preston investigate what is reflecting across the lake, the boat they drive is registered in North Carolina, where the film was shot, instead of Louisiana, where the film is set. (at around 53 mins)
When Preston carries Jessie out to his truck in the rain (with her wrapped in the green army blanket), the distance the driver's door is open varies between shots.