FYI, it all worked out beautifully. I admit, I had to leave the room a few times and let my friend handle it, but the dogs worked it out. Dexter is head over heels in love with Kasee and, although Kasee seems less smitten, she plays with him. He follows her around... Well, like a puppy, and every once in a while I'm sure I've caught her rolling her eyes at him.
Anyway, I know you kind of have to let the dogs work it out but I was afraid Kasee would get her much tinier button kicked. In fact, turns out that Dexter just wants her to like him. :-) I guess it's hard to predict the whole alpha thing.
I just wanted to let you know that it looks like it's all good. We do have to watch them around food - Dexter gets really hot if it looks like she's getting too close to his food but he's the same way with Jackie so that's not surprising.
Now, if we could just get Jackie to forget how to bark, life would be perfect...
Thanks for all your help!