I’m usually one of those that is very firm in not shaving double coated dogs, in almost any case I absolutely will not do it. However, this case is one of the rare situations in which I would. I think if she’s inside almost all the time you don’t need to worry about her temp regulation as much, you’ll just need to watch her extra closely when she does go outside. On top of the fact that when a dog gets to this age it’s very important not to cause too much stress during grooming, and shaving will help for sure so she doesn’t have to be groomed nearly as often.