When talking to my mother, I asked if she had any superstitions that she can think of. What she came to was something that I actually have noticed in her actions.
She said that, “Whenever I hear an ambulance, either outside or while I am driving, I catch myself scratching my head. I think this is me targeting my nerves and anxiety in hopes that whoever is in the ambulance, or who the ambulance is rushed too, is not someone that I know or am related to.”
Background Info: My mother mentioned that her mom was always cautious about ambulances and firetrucks, she did not scratch her head, but always would check the news to ensure that whatever emergency there was got resolved, or did not involve someone that she knew or was related to. This was clearly a superstition triggered by an emergency vehicle or situation.
Context: My mother told me about this superstition while at lunch over Passover weekend.
Analysis: This is something I have actually noticed my mom do, I remember asking her about it a while ago and she discussed with me how it is usually unintentional, but that it happens every time. This reminds me of my superstition of knocking on wood in a situation where I want to prevent an event.