When in survival mode on peaceful, mobs are spawning as intended until you are in splitscreen mode. Only existing friendly mobs are present, although donkeys appear to have disappeared. Cats are spawning fine in splitscreen but fish, squid and other wild mobs pigs, sheep etc do not seem to be spawning correctly. On a certain piece of water, the difference appears to be between single player and splitscreen modes. As soon as the 2nd player signs out fish visibly spawn immediately.