Maggy Moulach is a character from fairy folklore said to be a Highland Brownie. According to the folklore of Maggy Moulach, she had a son named Brownie-Clod, who was said to be a Dobie. A Dobie is a somewhat dull-witted, though well-intentioned, variety of brownie.
The tale mentions a certain Fincastle Mill, where none dare to go for fear of the brownies said to protect the mill from trespassers.
One night, a girl goes up to the mill as she does not have enough flour for her wedding cake. Because the miller has already left, she sneaks in to grind the flour herself. She puts on a pot of water to boil as she begins grinding the meal.
The Dobie who is guarding the mill, Brownie-clod, hears the commotion and finds the audacious maiden hard at work. Keeping his distance, he asks for her name, and the quick girl replies, "Oh, I'm Mise mi fein," which means, "Oh, I am me myself."
He again asks her name, but again she says "Mi fein." As he approaches her, she throws boiling water at him. He flees to his mother, Maggy Moulach, who asks who wounded him. Fatally burned by the boiling water, he gasps out "Me fein" (Me Myself) as he was told.
Maggy later finds out the trickery of the girl as she regularly brags to her friends of how she outsmarted a brownie. Maggy overhears the girl one day while walking past her window and takes vengeance. She throws a stool with such force that it kills the girl dead on the spot.
Another legend of Maggy tells how she finds a home near a farm. She is such a good worker that the owner of the farm fires all the farmhands in order to rely solely upon Maggy's work. This enrages her such that she goes on strike and becomes a Boggart, an entity similar to a poltergeist. She begins playing tricks on him until the farmer is obliged to hire back all the staff.
The story of Maggy Moulach's vengeance for her son could be seen as a warning against excessive pride. It could also be to remind the reader that there will invariably be someone who loves each of us, no matter our appearance, and will avenge the injuries inflicted.
The tale of Maggy Moulach and the farmer could be seen as a warning not to take those who help for granted.