Teen Who Survived 2017 Mass Shooting Dies in Calif. Boating Accident, Brother and Father Still Missing

• Johnny Phommathep II, 17, who survived the Rancho Tehama Reserve mass shooting in 2017, has died in a boating accident in California, the Sonoma County Sheriff's Office confirmed
• The late teenager's brother, Jake, 14 — who also survived the shooting — and their father, Johnny, are among the four who remain missing after the group's boat capsized off the coast of Bodega Bay on Saturday, Nov. 2
• "Our sincerest condolences to his family," the sheriff's office said on Facebook

A teenage boy, who was the victim of a mass shooting in 2017, has died and his younger brother and father are among four who are still missing after a boating accident in California.

On Monday, Nov. 4 at 4:45 p.m. local time, the Sonoma County Sheriff's Office shared an update on Facebook, revealing Johnny Phommathep II, 17, of Corning, had been found dead the day prior after the boat they were on capsized while they were crabbing off the coast of Bodega Bay on Saturday, Nov. 2.

"Our sincerest condolences to his family," the sheriff's office said.

The Facebook post had previously revealed that six people had been on the 21-foot white Bayliner boat at the time; three adults and three juveniles. 

One person was found alive, but four are still missing, police confirmed. 

Per the Los Angeles Times, KTVU and the San Francisco Chronicle, the teenager who died in the accident previously survived the Rancho Tehama Reserve mass shooting in 2017. Five people were killed and multiple others wounded in the attack at Rancho Tehama Elementary School.

According to the L.A. Times, Johnny survived the shooting along with his younger brother Jake, now 14, and mom Tiffany Phommathep. The outlet stated Tiffany took five bullets trying to protect her sons.

Following Saturday's boating accident, Jake remains missing along with the boys' father, Johnny's namesake.

While speaking to the publication, Tiffany said, “It’s really hard because both my sons, Johnny Jr. and Jake, they survived the Rancho Tehama shooting."

“We survived that and for them to come to their end like this....” she added.

"They've been through so much, both of my sons Johnny and Jake," Tiffany said, per KTVU. "Already one tragedy. They made that one, just to come out here."  

“The odds are not likely ... but I would like to hold on to hope that maybe they reached shore somewhere,” Tiffany told the L.A. Times.

Tiffany identified the other two missing adults as her husband's cousin, Prasong Khammoungkhoune, 45 — who was said to have owned the boat — and his longtime friend, Matthew Ong, 42.

According to KGO-TV, the boy who was found alive following the boating accident on Saturday was 11 years old and survived using a cooler.

"He self-rescued. He was able to make it to shore and stayed the night on the shore. In the morning, he walked up and was found by passersby on Highway 1 and he survived. It's really miraculous that he made it," Sonoma County Sheriff spokesperson, Misti Wood, said, per the outlet.

“The boat started taking on water so fast they didn’t even have time to radio for emergency service,” Tiffany told the L.A. Times of information she learned from the boy who had been rescued and officials. 

“They didn’t do anything else besides making sure everybody had a life jacket — and everybody had a life jacket,” she added, insisting the group were experienced boaters.

“He wanted to get into college, he wanted to be a pharmacist,” Tiffany said of her late son Johnny, who was a student at Corning Union High School. “He was such a good kid.”

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A GoFundMe set up by the school secretary at Rancho Tehama Elementary and a friend of the Phommathep family has raised over $37,500 as of Friday, Nov. 8.

The Sonoma County Sheriff's Office didn't immediately respond when contacted by PEOPLE.