By Jen Heger - Breaking Celebrity News Legal Editor

Mary Zahou says she’s “very disappointed” with the San Diego Sheriff's Department handling of her sister’s death which was ruled a suicide, something that the family refuses to accept.

Rebecca Zahau’s naked body was found hanging from her billionaire boyfriend Jonah Shacknai's mansion in Coronado, CA. (a suburb of San Diego), two days after his son, Max, 6, was found unconscious at the base of the stairs. Max later died from his injuries.

Mary Zahau is reeling from the stunning news that the twin sister of Jonah Shacknai's ex-wife and Max's mother, Dina, sent Rebecca a text message at 10:41 p.m. the night that her sister died.

In the message Nina Romano said she wanted to talk to Rebecca in person about Max's accident. "I'm very disappointed that the San Diego Sheriff's Department did not even follow-up on basic information such as the text message on Becky's phone," Mary tells Breaking Celebrity News.

Rebecca's cell phone hasn't been returned to her sister, who wants to turn it over to an independent forensic investigator. "I don't have anything they took. The San Diego Sheriff's Department is avoiding us and our attorney, Anne Bremner," Mary tells Breaking Celebrity News.

"I don't even want them right now other than to give the items to experts to