Commentary for Genesis 46:23

ובני דן חושים. At the time he moved to Egypt he had only this one son. The reason the Torah commences our verse with the word ובני, “and the sons of, etc.,” is as if the Torah had meant to say “and all the sons of Dan were only one, i.e. Chushim.” Similar formulations are found in Chronicles I 2,8 ובני איתן עזריה, where Azaryah, though the only son of Eytan, is described as part of Eytan’s children, i.e. בני.

ובני דן חושים, and the name of Dan’s children: Chushim. There were two, one of them died and his name has not been mentioned.