Calling it the toughest decision of their lives, two Wisconsin soldiers whose sister was killed in Iraq have decided against returning to combat.

Rachel and Charity Witmer (searchsaid Tuesday they were following advice from their commanders in Iraq, Gov. Jim Doyle (searchand the Wisconsin National Guard's Maj. Gen. Al Wilkening in requesting reassignment after their sister Michelle's death.

They said they were swayed by fears that the international attention they received since the death would put their fellow soldiers at risk if they rejoined their units.

"This we will not do," the sisters said in a statement read by family friend Joan Apt. The women were not present at the news conference announcing their decision.

The Wisconsin National Guard (searchis looking for suitable assignments for the sisters within the state so they can fulfill their active duty obligation, Guard spokesman Lt. Col. Tim Donovan said. The Army will have final say over where they are stationed.

"It's by far the most difficult decision we have ever made," the women said in a statement.

The New Berlin family's ordeal drew nationwide attention after the women's father issued an emotional plea to the military to spare his daughters from having to return to combat.

"I can't live another year like I've lived this one," John Witmer said at the time. "It's a burden I can't bear."

The sisters' grandmother, Jan Pretzel, said the decision was difficult for them because of their loyalty to their fellow soldiers. But Pretzel said their service in Iraq was enough for any family.

"I'm very, very proud of what my girls did," she said. "I'm ecstatic that they are going to be out of harm's way."

Spc. Michelle Witmer, 20, was with the 32nd Military Police Company when she died April 9 in an ambush in Baghdad. Rachel, 24, served in the same unit, while Michelle's twin sister Charity was a medic with the Guard's 118th Medical Battalion.

Under Pentagon policy, when a soldier is killed while serving in a hostile area, other close family members in the military may request a non-combat assignment.

The Witmer sisters said they "looked outside our family grief and considered the broader impact of our individual decisions."

Donovan said the Witmers will remain in their stateside assignments until they fulfill their active duty requirements.

Members of Rachel's unit were notified just after Michelle's death that their tour of duty had been extended 120 days. They had expected to return home in early May.

Rachel will likely be on active duty until August, Donovan said. Charity, a sergeant, arrived in Iraq in February and her unit's active duty is expected to expire after a year, Donovan said.

The women returned home April 12 for their sister's funeral and have remained on extended leave.

"No one can say that this family has not done enough to serve our country," Doyle said in a statement.