What is the significance of the ending of this short story "In the Wheels"?

Question

The short story "In the Wheels" (available in full at that link, perhaps a 10-15 minute read) is mostly about car racing with a speculative-fiction twist, but there's a surprising (to me) ending for the protagonist, initially a teenager living with his father, "Firstmother", and his father's young second wife Sara. The following quote is from near the end of the story:

Father died a year later. Firstmother crumpled up with grief and followed him into the grave in six months. Sara’s still a young woman, and she makes a good wife. My brothers and sisters that were her children have become my sons and daughters. Sara’s pregnant with the first of mine, and it looks like I won’t need a secondmother for many years.

Why did the author include this part - what does it add to the development or analysis of the character (or of the setting)? After what happened with the races, I could have imagined the protagonist either continuing life as a racer or settling down to a "normal" life like his father, perhaps marrying a local girl, but marrying his stepmother after his father's death? That was unexpected to me, and I don't understand the purpose of it with regard to the story.

Answer 1

I think there are a few things going on.

There are hints earlier in the story that Sara and Joseph have a connection. They are close to the same age; she keeps his secrets; she brings him food and touches his neck.

By the end of the story, he says "the farthest I want to travel is to the edge of my acres". He is interested in another girl, but only if she "shows up here". Sara is familiar and safe. After his experiences, he is not taking chances on anything more adventurous. Earlier in the story, Zeke says "You love being bad, breaking the rules, messing with magic." By the end, he rejects all of that in favour of safety and control. He has been all the way to Mexico, but he comes back to right where he started, and never wants to leave again. This shows how the events of the story affected him, and underlines how traumatic they were, adding to the horror of the story.

There is a 'like father, like son' theme in the story, for both him and Zeke. They both surpass their fathers, Zeke by channelling more magic than his father ever could, and Joseph by taking his father's wife as his wife. (Though I might be over-interpreting here.)

Also, in short stories, it's good to keep the number of characters low. We have Sara and Lydia, so what would introducing another love interest get us? Sara is kind of a Chekhov's gun in that way, as the connection between them was already established.