It has too many components to explain here in text, I have a video of me building it on my youtube and have included the blueprint so you can mess around with it in your own game.
Note: the timer is set to move fast for demonstration, change the timer to be longer by changing the number in the top arithmetic combinator, just make sure to also change the divisor in the bottom arithmetic combinator so that it outputs between 0 and 12 (current settings are 1200 top and /100 bottom)
Screen shots of the pet
blueprint