Dog won't stop pooping in house

My 12 year old dog is suddenly pooping in the house.... He does it either late at night or early in the morning. I took him in for a full physical, ran numerous tests, but the Doc said he was in great health. I think it is behavioral. He knows not to do it. I have tried positive reinforcement when he DOES go outside. But he won't stop doing it every night!!!! I have this vibe that he is angry about something. He is actually my parents' dog and I have been watching him for the last 5 months as they had to tend to family health issues. Does he miss them? Why is he acting up and how do I stop it? Thanks!

I think at 12 years old he might be starting to get incontinent. Old people have to get up in the middle of the night to go, so do old dogs. If he does it every night, set an alarm and get up to take him out. Yes, it's a PITA, but it's easier to do than cleaning up a mess and scolding a dog for doing something he quite probably can't control anymore.

He may be missing them too . When we had to move my 2 dogs slid backwards .

I agree.... just because a dog is potty trained in one house doesn't necessarily mean he's potty trained in another house.... no matter what their ages are you have to work on potty training at first to get them re trained.

But again, it's very likely also incontinence. There aren't really any tests the vet can run to test for incontinence.

Maybe talk to your parents about his schedule at their house.... what time did he eat dinner, what time did they take him out at night, did he poop at night, did he poop at other times of the day, etc. That will start to give you a better idea of what might need to be tweaked to get him to be able to hold it through the night.

IF, of course, it's physically possible for him to hold it through the night.

This is just a thought, but would it be possible to change his eating schedule so that his bowels are on the empty side at night? Charlie is a puppy, and he can't really hold it so we make sure all his meals are on a schedule before 6 pm, then make really sure he poos before bed, around 10:30-midnight. Otherwise we wake up for a stanky crate. I don't know if it would work the same way for an older dog, but if you can't hold it you can't hold it, right?

Is there a way you guys could install a dog door, so he can let himself out to go when he gets the urge?

Please be understanding. A 12 YO dog may be very upset by lifestyle changes, may be UNABLE to control himself, and is probably very uncomfortable with soiling inside the house if he has been trained for a long time. Being angry with him will not help the situation.

Some things to try:

Confine him in a smaller area at night. Maybe an expen, where you could put his bed and some papers so that he has somewhere to go during the night if he needs to.

Change his feeding time to earlier in the day so he has time to empty his bowels before bed time.

12 years old is geriatric in any breed, and sometimes this comes with special issues.