“my brothers.” Here, “brothers” refers to fellow Israelites, all of whom were descended from Jacob.
“made the heart of the people melt.” An idiom for frightened the people.” Some versions say, “made the heart of the people melt with fear,” but the emotions the people felt would not just be fear, but would be a mixture of fear, discouragement, etc. The word “heart” is singular and is a collective noun expressing how the people as a group felt.
“Yahweh my God.” Yahweh is Caleb’s God. There is no mention or implication of any God besides the singular and simple Yahweh. [See appendix 10, “Jesus is the Son of God, Not God the Son”].