The boys' mother, a Yorba Linda woman, was pulled from the water down the river near Vernal Fall in Yosemite National Park.
The boys were part of a church camping trip with Calvary Chapel East Anaheim. It was part of an annual getaway that began Monday. According to the church, the Adams family decided to spend the day in Yosemite Valley, while most of the rest of the campers were at Bass Lake for the day.
"When they pulled her out she just said 'My babies.' And at that point everybody realized this wasn't a time to cheer, there was still somebody in the water," said eyewitness Brent Foster.
Her two young sons, 10-year-old Andreas and 6-year-old Jacob, both swept away by the deceptively dangerous current.
Brent Foster captured the tragic scene Wednesday along the popular Mist Trail as he and his family were hiking. He says the boys' older brother tried desperately to save the 10- and 6-year-olds.
"He was apparently, according to my son, just shaken and bloodied, and he had his clothes ripped, and he turned to the many people apparently just standing there in shock and said 'Would you please pray for my brothers,'" said Foster.
At Calvary Chapel East Anaheim church, that's just what they did during a special prayer vigil Saturday night for the family, who are part of the congregation.
Foster joined dozens of others in mourning the loss of Andreas, who drowned, and Jacob, who is still missing.
"We're still praying that any hour they in park might call us or call the parents and say we found his body," said Calvary Pastor Bob Kopeny.
For many, the touching and emotional service cut close to home.
"It's a difficult time for the family, I can't even imagine what they're going through. I have two kids, 27 and 22, and I wouldn't even know how I would feel," said parishioner Patrick Selitrennickoff.
The boys' mother remains hospitalized in Northern California with back and foot injuries.
The search for the missing 6-year-old continues.
A fund has been set up for the Adams family. For more information, visit http://cc-ea.org/israel-tour/.