My dog has start to pee in the house.

Question
My dog (silky/chihuahua cross) is nearly 16 years old and has started to wee in the house even though she has used a doggy door all her life.  She tends to go outside during the day to pee but most nights she will just wee on the floor.  What can I do to stop her?

Answer
I'm guessing this is due to her age, Andrea. Where is she 'going' at? Is she leaving her sleeping area, going towards the doggie door, going into another room completely, etc.? Is the pathway to the doggie door well lit at night? Maybe putting a night light or two will help, if it isn't. It could be that her eyesight is not as good as it used to be, and she can't 'find' the door at night anymore. (long shot, but it's possible) She may also not realize she has to go during the night - she might not be waking up on time anymore.

Is she crate trained? If she is, then I would try crating her during the night and see if she 'goes' in the crate. If she doesn't whine or otherwise let you know she needs to go out, and instead just 'goes' in the crate, it may be a medical condition that the vet can help you with. If she >>doesn't<< potty in the crate during the night, then it's likely not a medical issue.