Newly adopted 5yo Shih Zhu poops in house

Question
I recently adopted a pre 5 yo Shih Zhu. She's recovering from spine surgery and her owners couldn't afford to pay the vet bills. We also have an 11 yo Carin terrier. They get along well.
The Shih Zhu was well-trained by her owners. She's great at telling us when she wants to go out and she's on a regular schedule. However, even if she has pooped outside, she has left us little piles. Is this spite or a call for attention? How do we correct it?

Answer
Hi Katthleen'
It may be neither.
It may be because of the surgery.
Could be her nerves are deadened a little, either from the damage to her spine that caused the surgery to be needed, or it could be it is hurtinr her too much to get to the door to ask to be let out, at that time.
Either the spinal damage, or the medications, if any that she is on, could be causing her to not be aware of the need to go, and she poops without realizing it until it is too late.
I would talk with her Vet about this orst.
If a medical reason, or deadened nerves is not responsible, then she may just be doing it to get more attention.
I doubt it is spite.
If she was with the other family for her whole life, she may be having some separation anxiety, or she may just be doing what she has always done, sometimes go out, sometimes go in the house.
Charlotte