Hard water vs soft water.
So many times we've been in a hotel room and I've taken a shower and commented on what soft water it is because it feels like the soap never rinses off and I feel slippery all over. She always tries to correct me by calling it hard water. She grew up in a desert city that has naturally hard water, so she'll always say, "I know what hard water is, I grew up with hard water!" when the "hard" water she grew up with was softened by some means. It doesn't matter how many articles and blog posts and ChatGPT sessions on the topic I show her, she always insists they're wrong and she's right. We argued about it a few times in the past, but now it's a running joke between us.
I randomly point at my cat and tell her, "YOU!! I know what you've done!" and then I run at her. She immediately goes WILD and starts tearing around the apartment and doing little lion roars. If I stop pursuit too soon then she'll taunt me by jumping over me on the sofa over and over again until I continue chasing her. When I "catch" her then she gives me a sassy slap in the face and scampers off.