|With your mouse right click on the helper assitant (in your case the dog) and select "choos a different animated character" then use the back and next buttons to cycle through the options then click on OK to select the one you prefer or cancel to not make a selection.|
You can also (if you want) turn it off completely.
OOPs sorry, I did not fully read the question I am not sure whether you can add other assistants. Also there is no future in it see here:
☺ When everything else fails, read the instructions.