The mother of Suleman Dawood, the teenager who died with his father aboard the Titan submersible, said she was supposed to take the trek down to the Titanic wreckage along with her husband, but stepped aside for her son.
“It was supposed to be Shahzada and I going down and then I stepped back and gave my place to Suleman because he really wanted to go," Christine Dawood told the BBC in an interview aired Monday.
She went on to describe the last time she saw her son and husband Shahzada Dawood before they boarded OceanGate's Titan submersible to view the Titanic wreckage 13,000 feet under the sea.
"We just hugged and joked actually because Shahzada was so excited to go down. He was like a little child," she said. "I miss them, I really, really miss them."
She added her son brought a Rubik's cube with him on the journey and was "so excited" to try to break a world record by solving it thousands of feet below the ocean.
Azmeh Dawood, Shahzada Dawood's sister and Suleman Dawood's aunt, previously told NBC News her 19-year-old nephew was "terrified" to board the sub, but ended up going because the trip fell over Father's Day weekend because he was eager to please his father.
"I feel disbelief. It’s an unreal situation," she said. "I feel like I’ve been caught in a really bad film, with a countdown, but you didn’t know what you’re counting down to."
The Titan sub went missing on June 18 on a dive to the Titanic. The U.S. Coast Guard announced on June 22 the discovery of debris near the famed ship's bow, saying the sub's voyage appeared to have ended in a "catastrophic implosion."
Shahzada and Suleman Dawood were among five people who were killed in the underwater disaster, along with OceanGate CEO Stockton Rush, Hamish Harding and Paul-Henri Nargeolet.
The Coast Guard said Monday it would lead an investigation into what caused the disaster, and is convening its highest investigative body, a marine board of investigation.
"The board will first and primarily work to determine the cause of this marine casualty and the five associated deaths," Capt. Jason Neubauer, chairman of the U.S. Coast Guard Marine Board of Investigation, said during a press conference on Sunday. "It can make recommendations to the proper authorities to pursue civil or criminal sanctions as necessary."
Authorities said they are reviewing voice and data recordings from the ship that chartered the sub to its launch point, as well as interviewing the 41 people aboard, which included family members of some of the victims.
Experts are focusing on the sub's carbon-fiber hull amid allegations Rush ignored warnings about the vessel's safety.
"They didn’t have any external bodies, governmental, otherwise overseeing what they’re doing," Andrew Norris, a former U.S. Coast Guard captain, told NBC News.
OceanGate, which has closed indefinitely, said in a statement it has "no additional information to share at this time."