CORONADO, Calif. - The most common crimes are small-time theft. Bicycles vanish from homes. Cell phones and other gadgets are stolen from cars and beach towels.

Residents of the wealthy San Diego suburb of Coronado - which features safe streets, world-class beaches and a small-town feel - are shocked by two mysterious deaths within a week, both tied to a historic mansion.

The first came when Rebecca Zahau, the 32-year-old girlfriend of Arizona pharmaceuticals tycoon Jonah Shacknai was found dead Wednesday, her nude body hanging from the balcony of his home, her wrists and ankles bound.

Two days earlier, Shacknai's son, Max, 6, who was being cared for by Zahau, fell down the stairs and was hospitalized. His parents said late Sunday that he died from his injuries.

Investigators say the son's death was an accident. They say Zahau's death is suspicious, but haven't ruled out suicide. Authorities repeated Monday they haven't established any link between the boy's fall and the woman's death.

Investigators identified the woman as Rebecca Nalepa, but court records show she changed her last name to Zahau in May after a divorce. Investigators declined to discuss evidence in the case.

"Suicides can appear odd," San Diego County Sheriff's Sgt. Roy Frank said. "It's not unusual to have a suicide that appears to be something else."

As shocking as the discovery of Zahau's body was, Marilynne Hartstein, a summertime resident from Scottsdale, Ariz., said it appeared to be a family or personal matter.

"People aren't afraid for themselves," Hartstein said on a morning walk.

Coronado draws many part-time residents from Arizona. They are known as "Zonies" - people who escape the Grand Canyon State's oppressive heat for California's ocean breezes.

Shacknai's 27-room home, known as the Spreckels mansion, is one of the more storied properties in a city of multimillion-dollar homes. It has unobstructed beach views and sits near Coronado's main street, which is lined with palm trees and upscale boutiques.

San Diego's gleaming skyline is across the San Diego Bay.

Zahau was at home with another woman, whom authorities won't identify, when Max fell down the stairs last Monday, Coronado Police Chief Louis Scanlon said. Paramedics found he wasn't breathing and did not have a pulse. He was treated at Rady Children's Hospital San Diego.

Scanlon called the boy's fall a "tragic accident."

Ted Greenberg, owner of Camp Diggity Dog, said Zahau called the Coronado kennel last Monday, shortly after the boy's fall, to ask that someone pick up her 14-month-old Weimaraner, Ocean. She said her child was hospitalized after an injury.

"She described it as her child," he said.

Greenberg went to the home Tuesday.

"She was crying on the phone on Monday and Tuesday she was quiet," he said.

Shacknai's brother, Adam, called 911 Wednesday to report that Zahau appeared to be dead, investigators said. The brother was staying in a mansion guesthouse. Jonah Shacknai was not at home.

On Sunday, Jonah Shacknai and his ex-wife, Dina, Max's mother, announced that their son had died from his injuries.

"His loving, kind and vibrant spirit will be forever in our hearts and those whom he touched every day," they said in a statement.

Jonah Shacknai founded Medicis Pharmaceuticals Corp. and has been chairman and chief executive of the Scottsdale, Ariz.-based company since 1988. In his divorce filing with Kimberly Shacknai, he filed a tax return that showed his income in 1998 at $16,991,304.

Medicis makes acne treatments Solodyn and Ziana and facial wrinkle treatment Restylane and Dysport, a competitor of Botox. Last year, the company earned $123 million on $700 million in revenue.

Shacknai has two children with his first wife, Kimberly, in 1993. The marriage was unhappy from the start, according to court-ordered family study written by psychologist John DiBacco as part of divorce proceedings.

The two met while working for rival pharmaceutical companies. Kimberly told a psychologist that their honeymoon was "terrible" because Shacknai questioned whether he had made a mistake in marrying her.

Still, she described Shacknai as "a very good father." DiBacco wrote that "it was quite apparent that his children are most important to him and he loves them dearly."

Max was Shacknai's only child with his second wife, Dina. The couple divorced in 2008.

Shacknai bought the 27-room 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.

In a 2005 article, The San Diego Union-Tribune said the main house includes six bedrooms, 4? baths, basement, attic and unfinished wine-storage room used during Prohibition. A guest house completed in 1928 has two master bedroom suites.

Shacknai clashed with historic preservationists after promising not to make major changes to the home.

The city granted Shacknai some exceptions - once to replace windows and another time to install French doors near the front entrance, said Mayor Casey Tanaka. The city rejected Shacknai's appeals to punch a window through the roof and attach a master bedroom.

"He was here enough where he felt like he was a fairly full-time resident," said Tanaka, 35, who serves part-time as mayor while teaching history at Coronado High School.

Zahau was an ophthalmic technician at Horizon Eye Specialists & Lasik Center in the Phoenix area from April 2008 to December 2010, said chief executive Michael Trier.

"Rebecca was a very experienced and skilled technician, who was well respected by her doctors, her co-workers and our patients," Trier said Monday. "We are saddened and troubled by the circumstances of her death.

A pot of flowers stood outside the Coronado mansion Monday with cards in her memory.

"It is the way you listened, the way you comforted, the way you related to my every heartache, my every victory, even my losses," read one note. "You were a true friend."

Associated Press writers Robert Jablon in Los Angeles, Amanda Lee Myers in Phoenix and researcher Rhonda Shafner contributed to this report.