Genesis 19:38, in the Targum's rendering:
"And the younger also brought forth a son, and she called his name Bar-Ammi, because he was the son of her father. He is the father of the Ammonite people unto this day."
Read this verse next to the previous one. The elder daughter named her son Moab — "from my father" — a name that openly declared what had happened. The younger daughter named her son Ben-Ammi — "son of my people" — a name that softened the truth into a euphemism. Her son was technically "of her people," but only in the narrowest sense: the only "people" she had was her own father.
The Talmud in Horayot 10b reads this linguistic distinction as a moral one. The younger daughter showed a kind of shame the elder did not. She gave her son a name he could live with. The elder daughter gave her son a name that would haunt him.
The Torah rewards the distinction in Deuteronomy 23:3-6. Both Moabites and Ammonites are barred from certain forms of entry into the Jewish community, but when Moses later commands the Israelites about how to treat these two peoples militarily, the Ammonites receive slightly lighter treatment. The rabbis connect this directly to Ben-Ammi's mother's slightly greater discretion.
This is the Targum's quiet insistence that words matter. The same act, named differently, produces different nations with different destinies. The children of Moab will shadow Israel with more hostility; the children of Ammon, somewhat less.
Both peoples, incidentally, will eventually be folded back into the redemptive story. Naamah the Ammonitess, wife of Solomon, became the mother of Rehoboam and a link in the Davidic line (1 Kings 14:21).
The takeaway: even in the same cave, the same night, the same sin, a person can choose how to name what they have done — and the naming will echo for a thousand years.