Hello all! I'm pretty new to the forums here but I figured this question might be okay to ask... My dog's 4.5 years old (approximately - age was estimated by a shelter) and I've been noticing increasingly that he's getting a good mix of white in the brown on his cheeks and in his "eyebrows". I'll try to get decent pictures to post later. Is this normal or is it too early? He deals with separation anxiety (and car anxiety, and anxiety around dogs, etc), so could it be an expression of too much stress in his life? A mineral in his diet that he's not getting? I don't really care what color his hair is, I just want to know if it is a reflection on his health. My understanding is that a 4 year old rat terrier is a young to middle aged adult... I could be wrong! Guinness is the first dog I've ever had and I don't necessarily know what to expect. I'd love to hear about your experiences!