John Gill Commentary 1 Chronicles 2:46

"And Ephah, Caleb`s concubine, bare Haran, and Moza, and Gazez; and Haran begat Gazez." — 1 Chronicles 2:46 (ASV)

And Ephah Caleb's concubine bare Haran, and Moza, and Gazez, an half-wife, or secondary wife; for though this man seems not to have had more wives than one at a time, yet he had concubines with them; we read of another after this, if not a third: and Haran begat Gazez; whom he so named after his brother.