I Am Smart Enough to Know I Don't Know It All

I know I don't, but my family thinks I do. Whenever they don't know something, they ask me. When someone else doesn't know something, they tell them to ask me. I usually know the answer, but when I don't, they are shocked and disappointed in me. Maybe it is part of why I feel I need to learn many things...even things I won't ever need to repeat.