Ok so last night I was playin with the girls, and noticed Duchess (basically aall white but with brown nose and hind area) suddenly has a very small patch of black fur under some of the white fur on her hind area. She is approx 6 months old now. Is she still able to develop different markings? I thot at first it was dirt but then realized it was real black fur in just one spot. I couldn't get a pic cuz she would not sit still. Any thoughts?