I don't have a childhood avatar for one simple reason. Alan (Hauser) gave me my roadrunner and John (walkingsouth) animated it.
I just love it.
Those childhood pics, in whatever form, are very important. They are a vivid reminder of our innocence and defenselessness and challenge us to acknowledge those facts. But they also confront us with feelings from boyhood that we may not have processed or "owned" yet. I wonder if that's why you cannot deal with your own pics yet. That is, they threaten to flood you with feelings that you have stuffed back for years.
Just a thought.