In real life, it took me several years before I finally was brave enough to walk through the Life in the Sea exhibit and not freak out in the presence of this monstrous blue whale hanging 30 feet overhead. By the time I was Peter's age here, I had finally overcome my initial fear, at least to the point where I could walk through the exhibit on field trips without freaking out anymore.
I still can't watch any movies or play games with deep underwater portions (there's not enough money in the world to get me to play Subnautica), but at least I know I defeated my fear of the whale.