As soon as I can find the USB cable for my camera I will upload some pics. I thought it was just acne at first, but in the last day or two she has had a bad "breakout" under her jowls on the side of her chin. She is about 15 months old.
I had a boxer pup and a great dane pup that both had the same thing. Vet called it puppy acne. I can't remember if he gave us anything to put on it or not but it went away on both with no future problems.
Could be puppy acne. All of my puppies have gotten puppy acne when they were younger. They also get acne after they've been shaved for shows if I haven't cleaned my clippers recently. Try cleaning the area three times per day with witch hazel, and wash his/her mouth after meals. If feeding from plastic bowels, switch to stainless steel, as plastic can harbour bacteria.