וְהַצְּעִירָ֤ה גַם־הִוא֙ יָ֣לְדָה בֵּ֔ן וַתִּקְרָ֥א שְׁמ֖וֹ בֶּן־עַמִּ֑י ה֛וּא אֲבִ֥י בְנֵֽי־עַמּ֖וֹן עַד־הַיּֽוֹם׃ (ס)
And the younger, she also bore a son, and called his name Ben-ammi—the same is the father of the children of Ammon unto this day.
Read kabbalistic (mystical) interpretation of Genesis 19:38: and classical mystical sources.