Sometimes this happens down through many generations. You will see the same surnames on militia rosters from the Indian Wars repeated for the Gulf War in the same community. Today it could be a mother, an aunt, or a sister. Back when I first joined, most new accessions were single. There was a saying then, that if the Air Force wanted you to have a family, they would have issued you one.
Families are our heart in other ways as well.
As soldiers, we are trained as warriors in the violent business of armed combat. Taken to its extreme, as we sometimes do in a wartime environment, this business can deaden our civilized sensibilities. Our family values provide the balance that can keep us sane and human in an inhuman time and place. They enable us to face the horrors of war with a sense of perspective and proportion. Thoughts of family are survival tools for combatants and prisoners.