The U.S. Army is investigating the possibility that Penich's death came as a result of friendly fire.
The family is not commenting until the investigation is complete.
Funeral for soldier killed in Afghanistan
BEACH PARK, Ill.
Twenty-five-year-old Army Sergeant John Penich was laid to rest in his hometown of north suburban Beach Park.
He was killed by gunfire on October 16 in Karangol Village, Afghanistan.
