Rebecca NalepaAfter a formal investigation, it has been determined that Rebecca Zahau, a woman who was found hanging naked from a second-floor balcony at a California mansion last month with her wrists and ankles bound, committed suicide.

See our original story on the bizarre death here.

Zahau’s sister, Mary Zahau-Loehner, confirmed the findings yesterday, saying she found investigators unconvincing during a visit to her home Wednesday in Missouri.

“It doesn’t add up,” she said. “Nothing adds up.”

Sheriff Bill Gore plans to hold a press conference today to discuss the investigators’ findings.

Zahau, 32, was found dead on July 13 at the mansion in suburban Coronado, two days after 6-year-old boy Max Shacknai, who under her care at the time, was seriously injured in a fall down the stairs. Max later died from his injuries.

The mansion belongs to Jonah Shacknai, an Arizona pharmaceuticals mogul. Zahau was his girlfriend of two years. Max was his son from a previous marriage that ended in divorce back in 2008.

More in the video below.