Is this something new, or has it been happening long term? If it is new, it could be a bladder infection and needs vet intervention before it turns septic. If it is long term it could be a weak bladder, and I am not sure what could be done for it. I am beginning to have the same problem with my 10 year old dobe, with occaisional incontenence when she sleeps.
There are only two things that I have found to help. I make sure that she goes outside and empties her bladder well just before bedtime, and I also will pad the couch where she lays most often, if I know she's having a hard time lately. Most chain stores carry those blue plastic and paper liners for wheelchairs and beds for people, and they are about 3' X2'. I put those under my couch throw that covers the seat of the couch. That way no one knows they are there, the rustling sound is muffled so it doesn't scare the dog, and the couch cover is easily laundered.
Niether of my suggestions will help the problem at the source, but can make living with it a bit easier.
I'm not laughing, either.
Stella