Dina Shacknai, the mother of six-year-old Max Shacknai who tragically died last summer at his father's Coronado mansion, is suing the San Diego Medical Examiner's office to obtain his autopsy photos because she doesn't believe that he died by falling and hitting his head, RadarOnline.com is exclusively reporting.

As we previously reported, Rebecca Zahau, the girlfriend of Dina Shacknai's ex-husband Jonah Shacknai, killed herself just days after Max's fatal accident.

The historic  mansion where Rebecca Zahau’s body was found hanged this summer has been sold by the billionaire owner Jonah Shacknai, who was her boyfriend at the time of her death.

Shacknai’s six-year-old son Max had an accident in the home on July 11, and two days later Zahau, 32, who had been taking care of the young boy at the time of his accident, was found hanging naked from a balcony of the historic mansion. 

Max tragically passed away a few days later and the San Diego Police Department and Coroner’s office controversially ruled Rebecca’s death a suicide.

The San Diego County Sheriff's Department still hasn't turned evidence in the Rebecca Zahau death case over to her grieving family, RadarOnline.com is exclusively reporting.

Zahau's tragic death was ruled a suicide after her nude body was found hanging from the outside of her multimillionaire boyfriend Jonah Shacknai's mansion in Coronado, California.

Rebecca's death occurred two days after Jonah's six-year-old son, Max, was discovered unconscious at the base of the stairs of the historic Spreckles Mansion they all shared. Max subsequently died from his injuries, and his death was ruled an accident.

As the mystery surrounding the death of Rebecca Zahau grows, another unexplained footprint has surfaced, in the bedroom where she was moments before she allegedly hanged herself RadarOnline.com has exclusively learned.

Dr. Maurice Godwin, a forensic expert hired by the Zahau family, told RadarOnline.com that a shoe impression on the carpet in the bedroom is unknown and may not have come from police but from someone else not yet identified.

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"The toe is actually underneath the foot of the bed," Dr. Godwin told RadarOnline.com about the shoe print in the photo given to RadarOnline.com that was part of the police evidence.  "This could suggest that it is likely not from the police."

Rebecca's naked body was found hanging from the balcony at her boyfriend Jonah Shackani's historic Spreckels Mansion in Coronado, CA in July, two days after his son, Max, 6 was found unconscious at the base of the stairs. Max later died from his injuries.

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Police have said that Rebecca hanged herself after receiving a distressing call from Shacknai telling her that his son's health had taken a turn for the worse.  They have said she was alone in the home, but her family disputes this assertion and have said they think she was murdered.

Forensic Expert Reveals Another Set Of Unknown Footprints On Balcony In Zahau Case

According to Dr. Godwin's examination there was an unknown shoe impression in the bedroom where the police have said Rebecca was before she hanged herself by tying a rope to the leg of the bed frame, which would raise a flag about someone else being in the room with Rebecca.

As RadarOnline.com previously reported, the renowned expert had harsh criticism for the San Diego Sheriff's Department's handling of Rebecca's investigation, and her family has repeatedly called for the authorities to re-open the case into her death.

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The new witness in the Coronado mansion deaths -- who is claiming they heard a "scream for help" hours before cops said Rebecca Zahau died -- attempted to report the information to police twice but was "blown off," RadarOnline.com has exclusively learned.

As we previously revealed, the informant, whose identity has not been released, contacted Zahau's anguished family on Wednesday and provided them with sensational information that could blow the suicide theory to pieces.

According to the witness, they heard screams from inside the Coronado, Calif., mansion at 11 p.m.

The family of Rebecca Zahau isn't giving up its quest to have the mysterious mansions death case re-investigated, despite the California Attorney General denying a similar request by the woman's pharmaceutical tycoon boyfriend to take another look at the supposed suicide hanging and coincidental fatal fall of his son.

The Zahaus are challenging the San Diego County Sheriff's Department's finding that Rebecca, 32, killed herself by binding her wrists and ankles and hanging herself naked from a balcony at Jonah Shacknai's historic mansion in Coronado, California.

As RadarOnline.com revealed, the family's high-powered lawyer Anne Bremner sent an email to California Attorney General Kamala D. Harris on Wednesday requesting a full and independent investigation because she had obtained "compelling evidence to be investigated" and "new critical witnesses to be interviewed."

Jonah Shacknai's young son Max, who was found unconscious at the base of the stairs at the family vacation home in Coronado, might have been suffocated, RadarOnline.com has confirmed.

Max's death was determined to be an accident by the San Diego Medical Examiner. Jonah's girlfriend, Rebecca Zahau, was found nude, hands tied behind her back, hanging from a balcony at the mansion, two days after Max's accident.

In search warrants that were just released by a San Diego judge, Max's doctor, Dr. Peterson at Rady Children's Hospital told the Coronado Police Department, "he did not feel the visible injuries were consistent with the cardiac arrest and brain swelling experienced by Shacknai. Dr. Peterson expressed concerns based on the above factors that suffocation may have occurred prior to Shacknai's fall."

California Attorney General Kamala Harris has formally denied Jonah Shacknai's request for the office to re-examine the deaths of his girlfriend, Rebecca Zahau, and son, Max, RadarOnline.com is exclusively reporting.

Rebecca's nude body was found hanging from a balcony at Jonah's Coronado mansion, two days after Max was found unconscious at the base of the stairs. Cops ruled Rebecca's death a suicide, something her family vehemently disagrees with.

EXCLUSIVE DOCUMENT: Read Attorney General’s letter Refusing To Re-Examine Rebecca Zahau Case

The polygrapher that gave Adam Shacknai his lie detector test, tells RadarOnline.com exclusively, that the results of the test were inconclusive, and that he recommended to the San Diego Sheriff's Department that another test be given.

Adam's billionaire brother Jonah Shacknai was dating Rebecca Zahau, who was found nude, and hanging from a balcony at the Medicis' CEO's mansion in Coronado, a wealthy suburb of San Diego.

Cops contend that Rebecca killed herself. Rebecca's family vehemently disagrees with the San Diego Sheriff's Department's conclusion that she committed suicide and are pushing for the investigation to be reopened.

The anguished family of Rebecca Zahau has formally asked the California Attorney General to launch a full and independent investigation of the woman’s mysterious hanging, RadarOnline.com has exclusively learned.

In an email sent to Attorney General Kamala D. Harris on Wednesday, the family’s high-profile lawyer, Anne Bremner, said the Department should open a new probe because she had obtained "compelling evidence to be investigated" and "new critical witnesses to be interviewed."

“I will be respectfully submitting to you a formal and detailed response to Mr. Shacknai’s letter (which was not copied to me nor to my clients),” Bremner wrote.