Yup, the dog. I was in bed yesterday when Mango came up and stood her front paws on my chest. A few hours later I noticed the pain. The good news is that the pain only lasts a few days. Ribs heal quickly enough. I know this because this isn't the first broken rib I've had since cancer came into my life, the last break was around Christmas. At the time, I blamed it on exertion while carrying the Kitchen Aid mixer up from the basement to make cookies.
This is life with Stage IV. Cookies, puppy kisses. Each risks a broken bone.