My little one isn't doing much more than cooing and crying, but we have some funny ones that still get told as family stories. My favorite thing is when they're still used 20+ years later without any thought, and then someone outside the family "catches" you using it, and the story lives on.
Examples from our family:
When I was 4, I didn't like the loud noises the "fireworkers" made on the 4th of July.
When I was told to finish my vegetables, I told my mom they were "too tasty."
When the "your momma" jokes came to our house, it somehow morphed into "Jo Momma," which got shortened to just "Jo." My mother still answers to "Jo" (her name is Faye!) which thoroughly confuses my husband.