CORONADO, Calif. (CBS 8) -- The sister of the woman found dead in a Coronado mansion is speaking out for the first time to News 8 about the tragic death.

"We are still trying to accept the fact that she is gone and has been taken away from us," said Mary Zahau-Loehner in a phone interview Monday from her home in Missouri.

Rebecca Zahau, 32, was found hanging from the balcony of the historic Spreckels mansion in Coronado on July 13, nearly two weeks ago. She was naked and bound at her hands and feet. Zahau died just two days after the 6-year-old son of her millionaire boyfriend fell off a stairway inside the mansion, reportedly while under Zahau's care, and later died.

Arizona tycoon Jonah Shacknai, 54, owns the oceanfront mansion where the tragic deaths happened and resided there with Zahau during the summer months.

"I don't think there's any words to express how we feel," Zahau-Loehner said. "My mother is distraught and we are trying to take it one day at a time, trying to be there for her. My dad hasn't spoken much at all."

Death certificates obtained by News 8 confirm Shacknai's son, Maxfield Aaron Shacknai, died at Rady Children's Hospital at 11:30 a.m. on July 16, five days after his fall near the stairs. The records reveal the boy was buried last week at Mt. Sinai Cemetery in Phoenix, AZ.

Rebecca Mawii Zahau was laid to rest at St. Joseph Memorial Park in St. Joseph, MO, according to her death certificate. Zahau-Loehner said her sister's funeral and burial services were held Saturday.

The cause of death on both certificates is listed as "pending," while the San Diego County Medical Examiner awaits the results of toxicology and forensic testing. Autopsies were performed on both bodies to determine cause of death, the records show.

Zahau-Loehner said the bizarre circumstances of those few days should in no way overshadow more than three decades of happiness her sister Rebecca brought to others.

"We as a family want people to remember she was a very special person who can make anybody smile," Zahau-Loehner said. "She has love and strength about her that can always comfort somebody and make them feel very special."

Zahau-Loehner said Rebecca had a unique style, always coordinating her makeup to match her outfits. She said the family knew her as Becky and that she was a fitness fanatic, who always embraced new challenges, like the triathlon she was training for.

"I said, ‘How do you possibly plan to do the triathlon when you don't know how to swim?'" Zahau-Loehner recalled. "That's when she told me she signed up for swim lessons."

And though they don't yet know how she died, the family holds on to celebrate the life Rebecca lived.

"She was full of energy, loved her life, loved God and loved her family," Zahau-Loehner said. "I think I want everybody to know that she lived her life to the fullest."