I've been trying for awhile now to hatch some better traits into my Polar Fox from my Dragon. However, all I ever get is another Dragon. Am I just unlucky or does the Polar Fox Really not like to hatch another Polar Fox? Or maybe a crown pet needs another crown pet?
For a time I thought Polar Fox was one of those pets that would not hatch into another Polar Fox. But that is not true. Since then, I have hatched one myself, and have a second generation Fox. So I would guess you just had a string of bad luck. It happens.