Hey I got my mice about a month ago and they are now about 14 weeks. But just today i have noticed that one of my mice has black patches on her fur. She is white and brown but now around her eyes and on the back of her neck her fur is turning black.I researched this but only computer things came up so I was just wondering if this is normal and I shouldn't worry about it or if it is an illness and she needs to be checked out. Thanks