Isaiah 9:6 tells us about Jesus: "a child will be born; a son will be given." But these phrases are not merely parallel. Yes, Jesus would be born as a child is born - one among a million. He shared in our flesh and blood. He walked in our shoes, so that he could die in our place. He fully identified with us so that he could bear our sins.
But Jesus as "son" is not just like us. Throughout world history, sons have disappointed, starting with Adam, "the son of God" (Luke 3:38), and then Adam's son, Cain. The reason that our sons disappoint is because they find that they are like their fathers.
But Jesus, like the king on the throne, is a son in a different sense. This is the one who is appointed by God to stand in special relationship with Himself, and to represent God to the people. Psalm 2:6,7 reads, “But as for Me, I have installed My King Upon Zion, My holy mountain.” “I will surely tell of the decree of the LORD: He said to Me, ‘You are My Son, Today I have begotten You." Historically, this refers to David, the king. But theologically, it looks ahead to Jesus.
And it is at this point that we realize that Jesus is the "son given" who is not just like us. He is the Son that we do not deserve, but the Son that we need.