SAN DIEGO (AP) -- The fatal fall of 6-year-old boy at a historic mansion was an accident and the hanging death of the homeowner's girlfriend was a suicide, authorities said Friday.
The findings in the deaths of young Max Shacknai and Rebecca Zahau, 32, followed a lengthy investigation.
"Were these deaths the result of criminal conduct? Was Max's death a homicide? The answer is no," San Diego County Sheriff Bill Gore told a news conference. "It was a tragic accident. Was Rebecca's death a homicide? Again the answer is no. It was a suicide ... These deaths were not the result of any criminal acts."
Zahau's sister had told The Associated Press on Thursday that she had been informed of the suicide finding.
When Zahau's naked body was found hanging from the mansion's balcony with her ankles and wrists bound, investigators were quick to say they weren't ruling out suicide.
The woman's sister said investigators confirmed that it was suicide during a visit to the family home in St. Joseph, Mo., to discuss their findings. They told her Wednesday that it would have been difficult but "very possible" for Zahau to kill herself.
Max had fallen down stairs at the mansion while under her care and succumbed to his injuries days later. Authorities said the last call to Zahau's voicemail before her death had delivered the message that the boy was in grave condition.
The woman and the boy are linked to Jonah Shacknai, an Arizona pharmaceuticals magnate who owns the 27-room waterfront mansion. Zahau was his girlfriend of two years. Max was his son from a marriage that ended in divorce in 2008.
Mary Zahau-Loehner said investigators failed to convince her that her sister killed herself. She said she spoke with Zahau the night before her body was found July 13 and she gave no hint that she planned to take her life. Zahau said she would bring Jonah Shacknai breakfast and a change of clothes the next morning to the hospital where his son was being treated.
Zahau also told her sister that she would call her parents in the morning on the way to the hospital. She emailed another sister in Germany to say she would be updating throughout the day.
"Too detailed planning for someone who's planning to end their life that night," Zahau-Loehner told The Associated Press Thursday. "It doesn't add up. Nothing adds up."
She said investigators told her there was no suicide note.
When Max fell down the stairs, Zahau was at home with a 13-year-old girl who was related to her, authorities say. He was hospitalized after paramedics found the boy wasn't breathing and did not have a pulse.
Two days later, Shacknai's brother, Adam, called 911 to report that Zahau appeared to be dead, investigators said. The brother was staying in a mansion guesthouse. Jonah Shacknai was not at home.
The home, known as the Spreckels mansion, is one of the more storied properties in Coronado, a small suburb of multimillion-dollar homes on the tip of a peninsula across a bay from downtown San Diego. The home has unobstructed beach views and sits near Coronado's main street, which is lined with palm trees and upscale boutiques.
Shacknai bought the mansion in March 2007, when it was assessed at $12.75 million. The home was built in 1908 and named for its original owner, John D. Spreckels, who also owned the newspapers, the San Diego Union and San Diego Tribune.
Shacknai founded Medicis Pharmaceuticals Corp. and has been chairman and chief executive of the Scottsdale, Ariz.-based company since 1988. Medicis makes acne treatments Solodyn and Ziana and facial wrinkle treatment Restylane and Dysport, a competitor of Botox.
He told investors on a conference call Aug. 8 that he would resume his normal work routine as soon as his children returned to school in Arizona.
"We've obviously had an extraordinarily difficult time. We have undertaken some tragedies, some losses that one couldn't imagine experiencing in a lifetime," he said.
Zahau, a native of Myanmar, was an ophthalmic technician at Horizon Eye Specialists & Lasik Center in the Phoenix area from April 2008 to December 2010. Her sister described her as a religious person.
Zahau-Loehner said there were many unanswered questions. Her family has hired Seattle attorney Anne Bremner.