John Gill Commentary Genesis 46:25

"These are the sons of Bilhah, whom Laban gave unto Rachel his daughter, and these she bare unto Jacob: all the souls were seven." — Genesis 46:25 (ASV)

These [are] the sons of Bilhah, which Laban gave to Rachel his daughter To be her maid, when she was married to Jacob: and she bore these to Jacob, all the souls [were] seven; not that she bore seven sons to Jacob, she bore but two, Dan and Naphtali; but the children of these with them made seven, one of Dan's, and four of Naphtali's, who went down with Jacob into Egypt.