A spokeswoman at University Medical Center says Ryan Collins died last night. The boy's grandfather, Bill Collins, said the boy had been kept on a ventilator for a time so that his organs could be donated.
Lightning struck a group of scouts taking shelter from a storm that blew through California's Sequoia National Park yesterday.
The leader, Steve Steve McCullagh, 29, was pronounced dead Thursday night, the Tulare County coroner's office said.
"It's just a tremendous shock to everybody," said Bill Collins.
Ryan Collins was declared brain-dead upon arrival. "He would never recover or anything else," his grandfather said.
Seven others were injured in the lightning strike, which came just four days after four men were electrocuted at the National Scout Jamboree in Virginia.
Meanwhile, the star-crossed Jamboree started anew Friday, after a week in which more than 300 people succumbed to the blistering heat while awaiting a visit from President Bush and four Scout leaders from Alaska died.
Mr. Bush's second attempt to visit the Jamboree on Thursday was postponed until Sunday, at the Scouts' request. Officials hoped to review safety procedures for large crowds and replenish supplies — including several tractor-trailers full of bottled water.
More than 300 Scouts and visitors were treated Wednesday at the hospital at Fort A.P. Hill, the Army base hosting the event, and some were airlifted to surrounding hospitals with heat-related illnesses.
As the heat subsided, more than 40,000 Scouts, leaders and visitors attending the 10-day event returned to a somewhat normal routine Thursday, going about daily activities like trading patches, going fishing and riding bikes.
On Thursday, CBS News Senior Producer Robert C. Dries, who was attending the jamboree, reported everything was back to normal.
"The weather is nice, a welcomed relief," said Dries. "The Scouts are continuing with their jamboree activities.
"Yesterday was ridiculous," said Jeremy Loftness, 15, of Denver, as he traded patches along the Army bases' streets. "I, myself, saw 50 people either passed out or being carried away."
The Scouts and the White House called off Mr. Bush's Wednesday appearance because of threatening storms. Shields said officials also didn't want to make the Boy Scouts and visitors remain in the intense heat, which reached the upper 90s with high humidity.
"Any alternative would not have been wise," Shields said.
The illnesses came as many still were reeling from the deaths of four Boy Scout leaders Monday. Some Scouts had been watching as the metal pole at the center of a large, white dining tent touched power lines, electrocuting the adult leaders. Screams rang out as the tent caught fire and the men burned.
An investigation into the accident was incomplete.
At the last jamboree four years ago, Mr. Bush's trip was also canceled because of bad weather, in which lightning strikes caused minor injuries to two Scouts. He spoke to the group a day later by videotape.
This time, Mr. Bush was expected to talk about the importance of Scouting and touch on the Monday deaths of four Scout leaders.
Many Scouts ate dinner at 2 p.m. and stood in long security lines to get a good spot in the open field to see what for most would be their first glimpse of a president in person.
Volunteers distributed water and ice by the caseload, and the Scouts were told they could remove their uniform shirts if they had another shirt underneath — a rarity for an event as important as a presidential visit, most Scouts said.
Soldiers carried Scouts on stretchers to the base hospital, located about three miles from the arena stage. Others were airlifted from the event while Jamboree officials called for emergency help from surrounding areas to transport Scouts during the storm, which brought high winds and lightning.
Some Scouts in Alaska had been watching as the metal pole at the center of a large, white dining tent touched power lines. Screams rang out as the tent caught fire and the men burned.
Killed were Michael J. Shibe, 49, Mike Lacroix, 42, and Ronald H. Bitzer, 58, all of Anchorage, Alaska; and Scott Edward Powell, 57, who had recently moved from Anchorage to Perrysville, Ohio. Shibe had two sons at the Jamboree and Lacroix had one.
Three adults were injured, and one returned to the Jamboree after being released from the hospital.