After seeing that my doubles didn't have the same dot patterns on the other side, I see that it is random because there are only 28 combinations of dots in a 6-6 set... which makes it less of an issue having doubles of the Pixar characters, as there are already 16 doubles of the dotted side in a full 44 set of these dominoes. (which means you could miss out on a complete set of 28 dotted dominoes if you have a lot of doubles of certain combinations)