John Gill Commentary 2 Samuel 15:22

"And David said to Ittai, Go and pass over. And Ittai the Gittite passed over, and all his men, and all the little ones that were with him." — 2 Samuel 15:22 (ASV)

And David said to Ittai, go, and pass over
It being his resolution to abide with him, he urged him no more to depart, but bid him pass over the brook Kidron before him:

and Ittai the Gittite passed over, and all his men ;
the six hundred Gittites that were under his command:

and all the little ones that [were] with him ;
that belonged to him and his men, and no doubt their wives also.