<human>: Provide a brief overview of the text.

My best friend just got a puppy about 2 months ago. When she did, her cat started peeing/pooping just outside the litter box. They're out of town right now and took their dogs (they have one older dog that they've had about the same time as the cat in addition to the puppy) to their friends house and I've been taking care of the cat. Last night she peed in the litter box and pooped on the floor. Tonight she peed on the floor and pooped in the litter box. Neither of us understand it and I am hoping someone has some advice or at least understanding as to why she's doing it. Thanks!
<bot>: Cat started peeing/pooping just outside of litter box since new puppy was introduced into the home. She still does some of her business in the litter box, but not all of it. Advice?