Growth of a Christian

I was listening to a good sermon a few weeks ago.The subject of growth caught my attention,There are many stages of growth in people just like school you have five subjects one child is better in math than another but both in the same grade,Christians are in the same class but some excel in different areas the reason for this is when a child is born they grow and sometimes they have not grown in attitude or social skills or other areas because they are still like a two year old in attitude because they have not grown yet past the stage of a two year old even though they are an adult sometimes something happened as a tragic that stunned their growth.