And they were married into the families of the sons of Manasseh— That is, according to the margin of our English Bibles, some who were of the families of Manasseh, from whom several families descended; for they did not marry promiscuously into any of the families of Manasseh, but into their father's family, which was the family of Hepher. Hence some would render the latter clause of this verse, in the house of the family of their father.
Related Commentaries of Numbers 36:12
Numbers 36:12
12 And they were married into the families of the sons of Manasseh the son of Joseph, and their inheritance remained in the tribe of the family of their father.