As he pulls on his boots, the giddy child fairly squirms with anticipation.

He'll soon be bouncing along on the horse's rump, holding on to his dad's belt loops.

"Pepito!" the boy cries when his dad comes through the door, mangling the Spanish for "Papacito," an affectionate term for one's father. "I'm ready to go!"

It is an image of sheer joy.

By the time of Vickie Castro's last conversation with Jonathan, his world was very different indeed. He was nursing a nagging, painful ankle injury that never received proper care, she said. His phone call from Iraq was hurried.

"I said, 'Jonathan, you sound exhausted.' And he said, 'Mom, it's pretty hard to do these 18-hour shifts, seven days a week,' " she said. "He said, 'I don't have a lot of time. I need to take a shower and go to bed.'

Jonathan Castro died this week in Mosul. By the time he made that phone call, he was to have been safely back in his Southern California home. He lived near the border of Orange and Riverside counties by the Cleveland National Forest, where he used to go riding with his dad.

He joined the Army before the Sept. 11, 2001, terrorist attacks. His initial four-year hitch was up June 28.

But one week earlier, he was issued a "stop-loss" order, which requires a soldier to stay on past his initial enlistment. Castro, a combat engineer who was an expert with explosives, didn't gripe, his mother said.

"He knew he signed that contract. He said, 'Mom, I read the small print. I know it's an eight-year commitment and they can keep me for eight years,' " she said.

A combat engineer in the Stryker Brigade, his Fort Lewis-based unit deployed in October. He became disillusioned, she said, by the Army's failure to back its mission with overwhelming force; by the huge profits he saw U.S. contractors making in Iraq; by the amount of oil he realized came with Iraq as a prize.

Today, Vickie Castro wants people to remember how good her son was. And in his short life, Jonathan Castro was a remarkable man. A remarkable boy, really.

A member of the Technical Education Club at Centennial High School, Castro built his own battery-powered car from the ground up and raced it in a national competition in Portland, Ore. He designed and built his own electric guitar -- even though he didn't know how to play it.

Castro's mother says his death should serve as a lesson.

"The whole nation should be sorry about that, and until we open our eyes to realize that, more and more of these wonderful women and men are going to lose their lives over there," Vickie Castro said. "We need to bring them all home. But we can't admit we're doing it wrong. So we'll keep sending more."