SAN DIEGO — When his son, Marine Lt. Nathan Krissoff, was killed two years ago in Iraq, Dr. Bill Krissoff found a unique way to honor his memory.

He closed up his lucrative orthopedic practice in Truckee, Calif., and, at age 60, joined the Navy medical corps in hopes of being assigned to Iraq to treat Marines and other military personnel.

It took presidential intervention to get Krissoff a waiver from the military's age limits on enlistees.

Now, Lt. Cmdr. Krissoff, 62, is on the verge of deploying to Iraq with a Marine unit. And on Thursday night, in his farewell address, President Bush included Krissoff among Americans who display "the best of our country — resilient and hopeful, caring and strong."

Krissoff's younger son, Austin, is also a Marine officer, now based at Camp Pendleton. He will soon return to Iraq for a second deployment.

Nathan Krissoff was killed Dec. 9, 2006, by a roadside bomb outside of Fallujah. Hundreds of Marines, sailors, soldiers and others attended an emotional memorial service at the Marine base at Fallujah where he was praised as a charismatic, courageous officer.

Now Bill Krissoff is attached to a medical unit assigned to the 2nd Marine Expeditionary Force at Camp Lejeune, soon to deploy to Iraq.

In his speech, Bush said that Krissoff "will help save America's wounded warriors — and uphold the legacy of his fallen son."

"If you lose a son or other family member, that's forever," he said. "When we lost Nathan, that put us on a different path. I'm not looking for closure.

"I'm just looking to do my part."