I'm not sure if this is a stupid question or not, but do Guinea pigs get thicker fur in the winter? Charlie is looking fluffier, or I might just be imagining it. I did switch her hay to KM, and I plan to get her on KM's timothy pellets as well as soon as they arrive. Could the diet change be making her look this way? I swear she's starting to look different though I'm just not sure what if it's not thicker fur.