...By the way, I don't know if your dog is capable of tricks like this but I'll tell you a story about mine....
If it was raining at night, and my dog didn't feel like going out, when I took her to pee, she would just "curtsey" and then turn round to come back again. I could always tell when she was playing this game because she slunk into the kitchen, didn't ask for her little treat, and went straight through to the other room. I'd take a piece of toilet tissue and wipe her, and it would come out dry!
I never made a fuss, just hitched her up to the leash again, and back out we would go! Until she did one for real!
I could always tell because then she'd come back all "happy dog" and shake when she got into the kitchen.
She never got away with trying this trick on me but she did try it sometimes lol!
To her way of thinking I guess she thought if she didn't pee, she would get back in quicker. It didn't work that way.
Even though they hate the wet grass, when you put them outside in the evening do you notice -does she actually pee? Or does she refuse to.
The reason I ask is because if she is refusing to, then wetting the bed is purely mechanical, and all you'll need to do is take her somewhere before bed where you can make sure she definitely pees.
But...for a housetrained dog to suddenly start doing things like this it's usually NOT behavioural.
Bed wetting suddenly in a dog who has never done that before, can mean a urinary tract infection, or early stage kidney insufficiency.
I would definitely get a urine sample, and take it and her to the vet for a check.
If it comes back as a UTI, then that usually is easily treated with a short antibiotic course. Also, ask for her bloodwork to be done, to be on the safe side.
My dog's ONLY symptom of early stage kidney failure was bed wetting and drinking more. The vet ran a urinalysis, said it was normal. Nothing wrong. But she wet the bed again the next few days so I took her back, and he ran a blood test. That was when her early stage renal failure was caught. It was treated successfully.
She since passed away of something completely unconnected. But her kidney values had come back to normal!
I have a 9 year old (estimate on age) Westie, Terrier and his bladder is "bullet proof", he can have his last pee at 9 PM and isn't particularly interested in going out at 8 AM. That is he can hold it for a long time. Older dogs, like people, find the need to "pee" more often than when younger.
Agree with Karla or, if an older dog, may be an inconiptinance issue
You don't state how old these dogs are, which would make a difference in what could be going on.........You need to rule out a Urinary Tract Infection, first.....Karla