I have rebuild the one, you see on the PIC, so it is more space for the ball at all. Also two holes for drainage were added. This dog house build by reddadsteve will fit perfect:
https://www.prusaprinters.org/prints/291-snoopy/
Printed without support, out of the Box with black PETG (PLA will be fine also, but was not loaded at this time)
The author remixed this model.