Answer: Yes, infants who die go to heaven. Babies are in the spiritual state of innocence because they don't know right from wrong. We become sinners through breaking the Law (1 John 3:4).
Paul said, "I would not have come to know sin except through the Law" (Rom 7:7).
Romans 3:20: "For through the Law comes the knowledge of sin."
Romans 5:13: "For until the Law sin was in the world, but sin is not imputed when there is no Law."
"To one who knows the right thing to do, and does not do it, to him it is sin" (James 4:17).
Babies cannot sin because they have no knowledge of right and wrong. When David's baby died he said, "But now he has died; why should I fast? Can I bring him back again? I shall go to him, but he will not return to me" (2 Sam. 12:23). David knew his child was in heaven and looked forward to being reunited with him.