What about Fear of water? Phobias: xenophobia definition is a bit simplistic; yes 'strangers' but also more towards the fear of foreigners. Usually, used socially and culturally than just 'strangers' but I digress.
Pinning to read later - Read this when you have time 1001 Character Quirks for Writing Fiction- I love this! It helps me create well-rounded characters! And once I know more about the characters, the plot seems to unfold by itself!