The Woman In White

La Llorona, Spanish for "the crying woman", is also known as the Woman in White or the Weeping Woman. In South American folklore, La Llorona is the spirit of a woman drying for her dead children. Children, which had typically been drowned by her. Her appearance is seen as an omen of death are are said to generally occur near bodies of water.

The story of the original Woman in White goes that she was a beautiful woman who married, or was seduced by, a local man with whom she had several children. Many names are given to her, including Sofia, Linda, Laura and María. The tale says that the man leave her for one of a few reasons: another woman, employment or simply to be away from La Llorona and the children. In order to spare the children a life of poverty, to free herself to find a new husband or simply to seek revenge on their father, La Lorona murders the children, usually by drowning.

Another version has the Woman in White being an Indian princess who fell in love with a handsome Mexican nobleman. She had two children by him, but he refused to marry her. He left her and married another woman. The princess went mad with rage and brutally murdered her children, stabbing them both to death. She was found later wandering the streets in a bloodstained dress and crying for her children. She was arrested and executed. It is said that her ghost still walks through the country at night in her bloody clothes, crying for her children. This version of the legend says that if she finds any children, it's likely that she would carry it away with her into the spirit world.

Sources:
La Llorona; Wikipedia
The Supernatural Book of Monsters, Spirits, Demons, and Ghouls; Alex Irvine