John Gill Commentary 2 Samuel 9:12

"And Mephibosheth had a young son, whose name was Mica. And all that dwelt in the house of Ziba were servants unto Mephibosheth." — 2 Samuel 9:12 (ASV)

And Mephibosheth had a young son, whose name [was] Micha
What his age was is not said. From him sprang a progeny of several generations (1 Chronicles 8:34–40).

and all that dwelt in the house Ziba [were] servants to Mephibosheth ;
his sons and his servants.