SANTA BARBARA, Calif. — A broken-hearted mother posted on her Facebook page Tuesday that her three daughters, their father and his wife were among those presumed dead after flames engulfed a dive boat off Southern California over the holiday weekend.

Susana Rosas of Stockton, California, thanked people for their prayers and support.

The family of five, celebrating a birthday with an activity they enjoyed, was among 34 people presumed dead in the blaze. All were sleeping below deck when the fire started early Monday. Other victims included students from a Northern California charter school serving grades 7-12, a high school science teacher and his daughter, an Arizona couple and a marine biologist who owned the diving company and was leading the tour.

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The bodies of 20 victims have been recovered so far. Many need to be identified by DNA analysis, and officials are collecting samples from family members.

Rosas posted that her three daughters — Evan, Nicole and Angela Quitasol — were on the Conception with their father Michael Quitasol and stepmother Fernisa Sison.

Evan Quitasol was a nurse at St. Joseph's Medical Center of Stockton, where her father and Sison had worked after attending nursing school at San Joaquin Delta College.

Sison also worked at the college teaching first-year nursing students full-time in 2005 and 2006 and later as an adjunct instructor, according to the school's spokesman, Alex Breitler.

"Everybody's devastated. It's a totally unexpected thing that happened," said Dominic Selga, Sison's ex-husband. "What caused the fire, that's the big question, that's what we all want to know."

Family Killed on Boat
From left: Evan Quitasol, Angela Quitasol, Michael Quitasol, Fernisa Sison, Nicole Quitasol, and Christina Sison. Family members told ABC10 that Christina was the only one pictured who was not onboard.
Susana Rosas

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Selga said his ex-wife's family had been on the boat "five or six" times and had been diving for a decade. Selga said the two families spent Mother's Day and Father's Day holidays together and called the Quitasols "great people."

Rosas' husband, Chris, told the Los Angeles Times that Nicole Quitasol worked as a bartender in Coronado near San Diego and her sister, Angela, was a science teacher at a middle school in Stockton.

The sisters were on the trip to celebrate their dad's birthday, Chris Rosas said. He described them as "the most kind, most loving people I've ever met — and I'm not just saying that because they're family."

Scott Chan, a physics teacher at American High School in Fremont, also was on board with his daughter, said Brian Killgore, a spokesman for the Fremont Unified School District.

The district said in a statement that Chan taught Advance Placement physics classes for the past three years at the school and was well-liked.

"His students knew him to be an innovative and inspiring teacher who developed a passion for physics among his students," the district said in a statement. "His loss is a tremendous tragedy for our school district."

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Chan said on his LinkedIn page that his teaching was fed by his "passion and wealth of real-world experience from research laboratories, and the electronics, computer, and high-performance automotive industries."

Also below deck were students from Pacific Collegiate School in Santa Cruz. School director Maria C. Reitano declined Tuesday to say how many students went on the trip, which was not sponsored by the school.

ABC affiliate KNXV-TV in Phoenix reported that an Arizona couple, Patricia Beitzinger and Neal Baltz, were also on the trip.

"They went to heaven doing something they loved together," Neal's father, John Baltz, told the station.

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Brett Harmeling of Houston said that his sister Kristy Finstad, 41, was leading the scuba tour off Santa Cruz Island, part of California's Channel Islands.

Harmeling thanked everyone in a post on his Facebook page for their "unconditional love and support during this incredibly tragic time."

Finstad was co-owner of Worldwide Diving Adventures based in Santa Cruz, which is about 250 miles (400 kilometers) north of Santa Cruz Island.

Finstad knew the area well, having done hundreds of dives in the Channel Islands, where she first swam with her father as a toddler. She first dove with a tank off Mexico at age 9, according to her company's website.

Harmeling described his sister to the Los Angeles Times as extremely strong-willed and adventurous.

"If there was a one percent chance of her making it, she would have made it," Harmeling, 31, said.

Their mother founded the diving company in the 1970s.

Finstad studied damselfish and corals in the Tahitian Islands, dove for black pearls in the French Polynesian Tuamotus Islands and counted salmonids for the city of Santa Cruz, where she lived. She also did research for the Australian Institute of Marine Science and wrote a restoration guidebook for the California Coastal Commission.

"My mission is to inspire appreciation for our underwater world," she wrote on her company's website.

She and her husband had just returned from sailing across the South Pacific. It was part of their 10-year plan that started on the back of a napkin in 2006.

They left from the Channel Islands in 2015 on the journey and planned to return in 2018. Before they set off, Finstad wrote: "Our new boss is King Neptune: when it blows we hunker down; when there's surf we paddle in; when there's rain we wash up. In terms of time-lines, the best we can do is point in the right direction."

The captain and four crew members awake on the upper decks jumped off the front of the vessel, swam to an inflatable boat at the back and steered it to a ship anchored nearby. Authorities have interviewed them but haven't said what efforts they made to help the 34 people trapped aboard before abandoning ship.

It appears the crew sent multiple mayday calls, including one from the Conception in which a crew member could be heard saying he couldn't breathe.

Investigators have received written accounts from the five survivors and would interview them, Brown said. The National Transportation Safety Board (NTSB), which also is investigating, said they were cooperating.

"I am 100 percent confident that our investigators will determine the cause of this fire, why it occurred, how it occurred and what is needed to prevent it from happening again," NTSB member Jennifer Homendy told reporters.

The Conception, based in Santa Barbara Harbor, was owned by Santa Barbara-based Truth Aquatics, founded in 1974. A memorial at the harbor has quickly grown as mourners come to pay their respects.

ABC10 sister station KEYT received the following statement from Dana Fritzler, who's married to the owner of the Conception, Glen Fritzler:

“The family is devastated. There’s no better captain than Jerry. No one. He kept everything on his boat immaculate and safe.”

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