I was really looking forward to reading Elizabeth Vargas's book about her struggle with alcoholism and it was excellent. Interestingly to me, she talked a lot about serious anxiety from age 3 or 4 and she remembers vividly at age 5, understanding that it was not okay to talk about those feelings. I had the same experience, and like her didn't even have a name for it at the time. Some of it is quite hard to read - as she says, she would do anything for her two young children, but she couldn't stop drinking for them.
Our deepest fear is not that we are inadequate. Our deepest fear is that we are powerful beyond measure. It is our light, not our darkness that most frightens us.