Sounds like the perfect opportunity to have the adult conversation about what constitutes a socially acceptable number of cows to have in your house. It's a very important conversation.
My dad used to live in the country, and a single cow got into a semi-abandoned old ranch hand house. (We assume some one left the door open. It was in there for a day or so.
That cow absolutely wrecked the place. Walls kicked in, windows smashed (frame and all), floors ripped up, table in 2 pieces, just an absolute disaster. Also, the poop.