Yes they do. When we lived with my wife's parents for a few months we both had separate D* service at the same address. In fact, it was a call to Directv that told me we could do that."RunnerFL" said:You'll probably have to have her cancel her account first. I don't believe they'll allow 2 accounts at the same address.
The best thing you can do is call them and ask how you should handle it.