What Happens to Babies that Die?

The churches that I spent my growing up years in were from the Assemblies of God and Covenant denominations. They were wonderful churches and I have good memories of the friends I made there. Besides my parents, the pastors and teachers in these churches built in me the faith foundation that I would take into my college years and beyond.

Almost all my life I have held the belief that man chooses God. I knew from the Bible that God reveals himself to people and as I got older I learned that the Holy Spirit played a role in our coming to faith, but I still believed that ultimately a person needed to decide for him or herself and say a prayer if they wanted to be saved.

One issue that was always problematic for me was the issue of children dying before they could make such a choice. I grew up learning the truth that all people are born sinful (in fact, it wasn't until my time in seminary that I even encountered the idea, albeit a heretical one, that a person could be born without being tainted in some form by sin and thus separated from God at birth). They idea of children dying, of abortion, and childhood disease made me wonder about the implications of such a truth. Surely God wouldn't send an infant or small child to hell for not accepting him into their tiny hearts would he?

The primary, and only plausible, memorable answer I ever got was one based on a concept called 'age of accountability.' This is the idea that in some form of divine mercy God doesn't hold people responsible for their sins until they can mentally comprehend their errors and their need for a Savior. A comforting concept for sure, but as I aged and I discovered that this theological security blanket called the 'age of accountability' is no where to be found in the Bible.

So I'm left wondering again about infant and child death. What happens to the eternal souls of these small children? Heaven or hell?

I'll post my current understanding in a few days. Until then, what do you think? And why do you think that?

PS - I would expect some kind of Biblical evidence and argument for such a weighty question. Thanks!