I've printed out the regulations and I'm going to be calling Northwest Airlines on Monday.
The only part I'm concerned about is that I'm accompanying her to my brother's for a vacation. But I'm not staying with her. So the question will be if Northwest is willing to provide me with a ticket, if they will also allow me to return to Boston while she's away (or make me pay for a return flight).
But I will keep you appraised of the developments as they play out.
Rita