Baptists like myself believe that children who are too young to understand what sin is, and the difference bewteen right and wrong go automatically to heaven when they die.
Please do not think I am being coarse or anything, I am trying to tell you that your son is happier now than he ever was on Earth because he is with Jesus right now! All his Earthly pains and troubles are forgotten already. He does think of you, people still remember their life on Earth, but he is in paradise right now!
Cherish your memory of him, it is supposed to hurt, that just means you loved him. But, do not fret or worry about where he is. He was just a small child. God never condemns those who are too young to be accountable for their sinful nature, He loves them and welcomes them with open arms!
So, be happy! Michael is in Heaven, looking down on us, hoping that we pay attention to what he sees God whispering in our ears right now!