bilbous, you are playing your character, and controlling the actions of that character. Are are not, and never will be that actual character. By what you are saying, typing your words on a keyboard instead of mentally controlling and existing as your character is OOC. Roleplaying is about playing the role of your characters, not -being- them.
And no, there is no great harm in pretending cats or other non-settings impacting things are in the game. As long as you remember that they are not, in fact, in the game, and no one else has to play along with it.