Brother of boat fire victim speaks out: 'Let the people in your life know that you love them'

"Kristy was full of love," her brother says.

Kristy Finstad, a 41-year-old marine biologist and diving instructor, was among 39 people aboard a dive boat that burst into flames early Monday morning near Santa Cruz Island, off the coast of Southern California.

Five crew members who were on the top deck of the 75-foot vessel jumped overboard when it went up in flames and were subsequently rescued. The other 34 people on board, including Finstad, apparently became trapped in the sleeping quarters below deck when flames blocked both a stairway and an escape hatch, according to the Santa Barbara County Sheriff's Office.

The U.S. Coast Guard called off the search for possible survivors on Tuesday, after the charred boat sank in 65 feet of water and overturned. The remains of at least 20 victims have been recovered so far and autopsies have not yet started, according to the sheriff's office. Finstad's family are among those still waiting for confirmation on the fate of their loved ones.

The incident and the cause of the fire remains under investigation.

"Whatever happened to my sister, she's wherever she needs to be -- as hard as that is to think about," Finstad's 31-year-old brother, Brett Harmeling, told ABC News in an emotional interview that aired Wednesday on "Good Morning America."

"I know that if she did transition [to death], that she did it doing something that she was passionate about and loved doing brings a bit of ease to me," he added. "That’s the only thing that brings me the peace to move through what’s going on."

Finstad was the co-owner of Worldwide Diving Adventures, her family's Santa Cruz-based scuba diving company that chartered the ill-fated ship. She was the divemaster on that excursion, according to her brother, who described her diving experience and knowledge as "incredible." A biography for Finstad on the company's website says her first dive was as a toddler, tucked under her father's arm, in the waters surrounding California's Channel Islands.

"She's very serious about safety. She's dove thousands of times," Harmeling said. "She had a survival skill set that many don't have, and I know that if there was even a 1% opportunity for her to make it out, that she would have."

Harmeling described his sister as "skilled, intuitive, vibrant, loving," and "compassionate." He said he finds comfort knowing that, "no matter what happened," she lived "a really deep and rich life."

Harmeling, who works as a financial representative in Houston, said practicing yoga and meditation, as his sister did, is helping him through the tragedy by guiding him to "see past all the things you can't control and to be grateful that you even had the opportunity to spend time with that person that you're now missing."

"Love the people that you have in your life because you don’t know when their time is up," he said. "Let the people in your life know that you love them and just cherish every moment, breath by breath, because it’s really precious."