A Rumor of Angels
Though she carries a side by side double barreled shotgun, we hear the sound of a pump action and she fires a third shot with no sound of reloading.
In the scenes where they are looking for James, the rainfall is inconsistent. It is alternately raining and not raining. The sun also appears and disappears.
Though she writes her son's messages after he dies, the Vietnam war was over in 1972, so there was not a Battle of Haiphong in 1974.