poop factory

noun2

1. •
   (humorous) An infant.

   • She didn't feel pushed aside because the colic-stricken poop factory needed to be changed and burped again. — 2010
2. •
   (humorous) An animal whose defecation inconveniences humans.

   • Ducklings and chicks grow at a phenomenal rate, consuming a huge amount of food. And what goes in, must come out. […] They are pecking, peeping poop factories. — 2004