David, I am not sure if you have reflected on the full nature of covenant theology from both a Reformed Paedobaptist and a Reformed Baptist perspective. You might find both these fairly brief books helpful "Covenants Made Simple: Understanding God's Unfolding Promises to His People" [Paedobaptist] and "Covenant Theology: A Reformed Baptist Perspective" [Baptist]God is able to do a miracle in them to have them regenerated and saved. Just would be done apart from the Infant baptism.