Were Naaman and Ard the sons or the grandsons of Benjamin?
They were the sons of Benjamin
And the sons of Benjamin were Belah, and Becher, and Ashbel, Gera, and Naaman, Ehi, and Rosh, Muppim, and Huppim, and Ard. Genesis 46:21
They were the grandsons of Benjamin
The sons of Benjamin ... Bela ... And the sons of Bela were Ard and Naaman. Numbers 26:38-40