This little bit of information I did not know about and probably explains why you end up with a different color bear in the family.
"During the breeding season, most sows will experience multiple ovulation or “heat” cycles. Interestingly, these cycles seem to continue even if the female is already pregnant. This provides sows with ample opportunities to mate, and may afford them the advantage of breeding with multiple males. Giving birth to cubs with different sires in the same litter increases genetic diversity in the offspring, which can improve the odds of adding healthy new bears to the population. This polyestrous (multiple cycles) strategy would be problematic if it produced pregnancies at different stages, but bears accommodate with an adaptation known as delayed implantation.
Ref
http://www.bear-hunting.com/tactics?...C-3FD0CF20CB53 (not a secured site but I am still up and running)