Sara María Aldrete Villareal was born on September 6, 1964, in Matamoros, Tamaulipas, Mexico. She grew up in a border town and attended high school in Brownsville, Texas. While living in Mexico, she gained resident alien status to enroll in Texas Southmost College. Sara was known as a good student among her peers. She stood at 6 feet 1 inch tall and studied physical education. Her goal was to transfer to a university and earn a teaching certification in physical education.

As Sara pursued her education, she became involved with Adolfo Constanzo, a Cuban American serial killer and cult leader. He introduced her to beliefs in witchcraft and dark magic. He gave her the nickname "La Madrina," which translates to "the godmother." Constanzo initiated her into his cult, which combined elements of Santería, Aztec warrior rituals, and Palo Mayombe. This cult engaged in practices that included blood rituals.

Constanzo made Sara his second-in-command. He directed her to oversee their followers while he managed drug trafficking activities, shipping marijuana into the United States.

Sara María Aldrete Villareal was involved in a series of brutal murders linked to a cult led by Adolfo Constanzo. In the late 1980s, their cult practiced a mix of dark magic and human sacrifice. Many of the victims were drug dealers who were killed for their body parts, which Constanzo used in rituals.

In 1989, the police began investigating a string of killings tied to the cult. The case drew national attention when they kidnapped Mark J. Kilroy, an American student. After Kilroy's abduction, police discovered evidence of the cult's activities, including human remains at their hideout, which was known as their 'shrine.'

On May 6, 1989, police located the cult's base in Mexico City. A shootout occurred, resulting in Constanzo and one of his followers being killed. Following this, Aldrete was arrested. In 1990, she faced charges of criminal association and was sentenced to six years in prison. Later, she was tried for her role in the killings and sentenced to 30 additional years in prison. If she were ever released, American authorities planned to charge her for the murder of Mark Kilroy.