Mystery Mansion Death: Family Shocked, Devastated

July 15, 2011— -- The family of Rebecca Zahau, who was found dead Wednesday at a historic mansion in Coronado, Calif., are shocked and devastated at her mysterious and unexpected death.

Authorities discovered Zahau's body on Wednesday after a houseguest, Adam Shacknai, told police he found her completely naked with a rope around her neck hanging from a balcony off the main house.

Zahau's sister Mary Zahau-Loehner, 33, told ABC News she spoke with her sister around midnight Tuesday, and everything seemed to be OK.

"She was normal, fine, just getting ready to go to bed," said Zahau-Loehner, who lives in Saint Joseph, Mo.

Zahau's ex-husband, Neil Nalepa, told ABC News affiliate KGTV the news was overwhelming. "I'm just trying to wrap my head around it," he said.

When police arrived at the historic Spreckels Mansion, owned by Shacknai's brother Jonah Shacknai, Zahau's multimillionaire boyfriend, they found the 32-year-old's body on the lawn in the backyard. Shacknai told them he had cut her down.

Police announced today that an autopsy has been completed and they are still awaiting results from the forensics investigation and lab work. They continue to investigate her mysterious death at the 27-room estate where her boyfriend's 6-year-old son suffered a severe injury just days before. All records will remain sealed during until the investigation is completed, police said.

"This is a very bizarre death, there's no doubt about it," San Diego Sheriff's Capt. Tim Curran told reporters regarding Zahau's death.

Even so, police cannot say if will lead to a criminal investigation.

"There are some very unique ways" people might kill themselves, Curran said. "If it was determined to be a suicide, people will do some very bizarre things."

Adam Shacknai is thought to have been the only person home, and may have been the last person to see her alive, investigators said.

Zahau-Loehner said she too believes Adam Shacknai was the only other person in the house at the time.

Since 2007, the mansion has belonged Jonah Shacknai, the 54-year-old multimillionaire founder and CEO of Medicis Pharmaceutical Corporation in Scottsdale, Ariz. – a company that makes treatments for acne and facial wrinkles.

He is grief-stricken, Zahau-Loehner told ABC News.

"They were together for two or three years and I think they were happy," she said. ""She goes to that Coronado house with his kids, they go there in the summertime."

Zahau's hands were bound behind her back and her feet were bound, but her hands and feet did not appear ever to have been bound together, police said. Though Adam Shacknai said she was hanging from a rope, investigators did not disclose what kind of material bound her hands and feet.

The home's balcony, which lies outside of a bedroom, is about 10 to 15 feet from the ground. Police were not immediately aware how Zahau's body would have been anchored if, indeed, it had been hanging.

If it was a suicide, it was unclear how Zahau could have hung herself while also binding her hands and feet.

Earlier Activity at Spreckels Mansion

Zahau's death caps an eventful week at the mansion.

On Monday morning, police received a call to the mansion from a woman they would not identify requesting medical aid for a 6-year-old boy, the son of Jonah Shacknai. The mother of the boy is believed to be Shacknai's ex-wife.

The child "had fallen from stairs and was not breathing and did not have a pulse," Coronado Police Chief Louis Scanlon said Thursday.