Shem would be the father of five sons, and many grandsons. The only ones listed here are the ones from before the Tower of Babel incident. This is probably because they couldn’t keep track of each other any more after that, due to the language barrier. One son may have spoke Chinese or Afrikaans, while another spoke Gailic or Egyptian (etc.) And, there weren’t any translators.
It is unknown whether Elam, Asshur, and/or Lud had any sons. Since the human race was highly prolific at this time, it seems likely they did. But, it would have been after the Babel incident, so the trackers of genealogies at this time didn’t know about them.
Arpachshad fathered Shelah, who in turn was the father of Eber, the father of the Hebrews (the name Eber is where the title Hebrew comes from.)
Eber had two sons, Peleg and Joktan. When Peleg was young (and Joktan wasn’t born yet), the Tower of Babel incident occurred: the earth was divided into nations by God changing their languages, so they couldn’t understand each other.
Joktan is the other son of Eber. Since his lineage is not the seed line, it is shown and then dismissed. But, he certainly kept his wife busy, with his thirteen sons (and who knows how many daughters!)
Peleg’s lineage will be discussed when I get to Genesis eleven, because he is the continuation of the messianic lineage of Jesus.