Hello!
My 2 1/2 year old dog(with long intervals in between)manages to empty her entire bladder in her bed! I can only relate to the circumstance of her drinking lots of dirty puddle water when out on a walk on the moors & coming home thoroughly exhausted. I always give her filtered water in her bowl----do you think this is of consequence? No signs i.e of other excessive drinking at home or being off colour but these 'one off' occasions--maybe her hormones acting up!
Any thoughts would be appreciated-has anyone experienced the same problem?

It could be she is about to start her season or if she is spayed it could be a hormone problem and you will need to see the vet for some HRT. On the other hand she may have a bladder infection.

I had a dog and a cat that peeded on their beds, I was told to feed them on the place they peed (in their bowls!).After that neither one of them ever wet on beds again. But you must make sure its not a medical reason she carn't hold on.