John Gill Commentary 1 Chronicles 2:31

"And the sons of Appaim: Ishi. And the sons of Ishi: Sheshan. And the sons of Sheshan: Ahlai." — 1 Chronicles 2:31 (ASV)

And the sons of Appaim; Ishi. And the sons of Ishi: Sheshan ,
&c.] Though they had each of them but one son, yet the plural number is used, their posterity being included, as in (1 Chronicles 2:8) and so in the next clause:

and the children of Sheshan; Ahlai ;
who, from (1 Chronicles 2:34 1 Chronicles 2:35) appears to be a daughter.