How old..?

How old do I have to be before I stop feeling like a child around my parents? At age 35 I still allow them to make me feel like I am a twelve year old who has done something wrong. Last week my husband and I went on vacation. We actually traded houses with my parents and they came down here to watch the children. The entire time I was in my mother's house, I had this fear that I was going to mess something up. I actually bleached a towel and I was like a scared child when I called my mother to let her know what happened. I am an adult! I am the mother of two, I have been married for almost 11 years and I own my own home. How is it that in one fail swoop of a sentence (or even a word) my mother can make me feel so small and insignificant. I know, I know these are my issues but my goodness how old will I have to be before I get past them?