Joseph. "The fruitful vine" (Genesis 49:22) has two tribes (not merely "families"). Thus Joseph has "the double portion" (1 Chronicles 5:1; 1 Chronicles 5:2).
Ephraim. Blessed first (Genesis 48:19; Genesis 48:20), is here named first, and is increased more than Manasseh (Deuteronomy 33:17). But in journeyings his numbers were diminished by 8,000. See Numbers 26:37, and compare 1 Chronicles 7:20-22.