Revealing mistake: In the closing scene, you can see the modern curb & sidewalk have been covered with dirt.
Revealing mistake: Following their escape from the comancheros, the two wheeled wagon driven by the old woman had a set of reins coming through the slats beneath the seat indicating that the old lady held fake reins and the wagon/horses were controlled by someone inside. Later, when they left the small town and headed to her son's ranch, a little window had been cut out of the slats where the control reins came through, no doubt to improve visibility and horse control.
Revealing mistake: When the children stay with the tribe, all of the horses being ridden, although shown having a saddle blanket, actually have saddles under those blankets.