Hearing noises at 2 am

When you have a new puppy that needs to be let out to potty and play before sleeping again, naturally, outside is a good place. So, sitting in my chair trying to get her to fall asleep, I hear crunching noises just past the backyard wall. The thing is, we live on a mountain, where coyotes and mountain lions live, and there's an undisturbed natural space between neighbors. Often, you can hear the coyotes at night, and supposedly the mountain lions don't come down our street, they stay one street up. I bring my other big dog outside with me to warn me of such noises, but nope, not this time. He didn't hear anything, but I could hear that rock being stepped on! Immediately, picked up the puppy and ran inside.

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