When my sister and I were young, mom and dad used the euphemism for pooping, “Shoot a big Rabbit”. To this day I have no idea where that came from. I Googled the phrase and the closest the internet came up with is an old English expression for farting. “Shooting Bunnies”. Mom spent a lot of time during WW II in London so it’s possible it migrated from that. With all the stories that mom and dad told us over the years, the etymology of “Shoot a big Rabbit” never came up. I regret never asking before either of them took it to their graves.