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In chapter 12, the creature describes the impressions he gains from watching the family. He is initially at a disadvantage because he does not speak their language, but he learns it by listening to them speaking amongst themselves. He considers them to be “lovely creatures” and soon realizes that they are unhappy because they are very poor. He had been gaining his own sustenance by stealing their food at night, but when he realizes how little they have, he stops doing that.
The creature is also moved to behave kindly by the kindness that he observes among them, as the younger people go without so that the old man can eat. The creature explains his new patterns of behavior, motivated by his realization that he had “inflicted pain on the cottagers.” From that point forward, one way he showed kindness was by gathering his own food. “I ... satisfied myself with berries, nuts, and roots, which I gathered from a neighbouring wood.”
In addition, the creature decides he wants to do more to help the family. He begins doing chores for them without their knowing who was responsible. He realizes that getting firewood, which they need for cooking as well as warmth, is a time-consuming process. He starts borrowing their tools and chopping and collecting wood, which he leaves at their doorstep. It gladdens his heart to see what a benefit this gift is to them, as the man can now spend time on other chores.
[D]uring the night, I often took his tools, ... and brought home firing sufficient for the consumption of several days.
[W]hen she opened the door in the morning, [she] appeared greatly astonished on seeing a great pile of wood on the outside. She uttered some words in a loud voice, and the youth joined her, who also expressed surprise. I observed, with pleasure, that he did not go to the forest that day, but spent it in repairing the cottage and cultivating the garden.