Who was the child in Isaiah 7:14 and 9:5-6.

Targums saw child of 9 as Messiah, which implies same for child of 7. By multiple fulfillment (a prophecy can go through more than once) it would be both Hezekiah, son of Achaz, and Jesus. What two other major prophecies are found in Isaiah? In 11, Messiah will have the Divine Spirit; in 53, He will suffer terribly.