In answer to these two questions, I offer two excerpts from Professor William Lane Craig’s articles. Here is the first, taken from How Can Christ Be the Only Way to God?:
God in His providence has so arranged the world that those who would respond to the Gospel if they heard it, do hear it. The sovereign God has so ordered human history that as the Gospel spreads out from first century Palestine, He places people in its path who would believe it if they heard it. Once the Gospel reaches a people, God providentially places there persons who He knew would respond to it if they heard it. In His love and mercy, God ensures that no one who would believe the Gospel if he heard it is born at a time and place in history where he fails to hear it. Those who do not respond to God’s general revelation in nature and conscience and never hear the Gospel would not respond to it if they did hear it. Hence, no one is lost because of historical or geographical accident. Anyone who wants or even would want to be saved will be saved.
And the second is taken from Middle Knowledge:
That brings us to Steve’s opening question. I included this one because many have mistakenly ascribed the view he defends to me. I don’t think, Steve, that your solution to the problem of persons who die in infancy (which is just an instance of the general problem of the fate of those who never have the opportunity to freely respond to the Gospel) is acceptable. For it would be immoral to judge a person, not for things he has done, but for things that he would have done under different circumstances. Had I been born in Nazi Germany, I might have been an ardent member of the Hitler Jugend and maybe even participated in atrocities. Under other circumstances, I might have been a thief or a terrorist. Am I therefore morally culpable for such acts? Well, of course not, for I never committed them! The difficulty with your solution becomes especially evident when you reflect that a person who died in infancy would have done different things under different circumstances. I’m not suggesting that those who die in infancy all suffer from transworld damnation. Under some circumstances those who died in infancy might have grown up to become wonderful Christians; under other circumstances, they might have joined the Internet Infidels. So how could God judge them for the different things they would have done under various circumstances?
So God will judge people on the basis of what they actually do. Re-read Matt. 11.20-24, and I think you’ll see that it doesn’t contradict that principle.
I accept, then, the “age of accountability” solution. God judges people on the basis of their response to light that they have. Infants have, so far as we know, no access to any divine revelation and hence are not held responsible for any response.