The sources say Marie slaughtered the horse for food when other provisions were exhausted, and that she used the hide for shelter.

This is described without drama in the more reliable secondary accounts, as a practical decision made in response to material necessity.

A horse that can no longer carry two children and a loaded pack over deep snow is still a substantial source of food and raw material.

The decision to kill it represented a transition from mobile to stationary survival, at least temporarily.

The Blue Mountain winter of 1814 was the kind of environment in which the specific knowledge that Marie carried mattered more than any other variable.