The women were best friends who served together in the 507th Maintenance Company from Fort Bliss, Texas. They were also roommates at Fort Bliss and tentmates in Iraq.
"Many of you may know our story, but what you may not know is what a great friend Lori was, what a great mother she is to these kids, what a great daughter she is, and what a great devoted soldier she was," Lynch said at a news conference Tuesday. "She taught me so much and knowing her made me a better person."
Piestewa, a member of the Hopi Tribe and single mother of two, is believed to be the first American Indian woman killed while fighting for the U.S. military.
The 23-year-old Piestewa died and Lynch was captured March 23, 2003, in an attack near the southern Iraq city of Nasiriyah. Soldiers rescued Lynch April 1, 2003; the videotaped rescue made her an international celebrity.
Lynch is recovering from injuries that included a broken back. She still walks with a cane. She has enrolled at West Virginia University and hopes to become a kindergarten teacher.
With proceeds from a $1 million book deal, Lynch created the Jessica Lynch Foundation to help Piestewa's two children. She later expanded the foundation's mission to educate children of military veterans and casualties.
"We love her like a daughter," said Terry Piestewa, Lori's father. "We know she was blaming herself for what happened. She was blaming herself that she didn't bring Lori home.
"She wants to be there for the kids. It's good for her, helps her heal."
On Wednesday, Lynch attended a sunrise ceremony held on Piestewa Peak, a north Phoenix mountain named after the fallen soldier. She is scheduled to visit Piestewa's hometown of Tuba City on Thursday, and visit her grave on the Hopi reservation in northern Arizona.