Another Update
Alas, as it turned out, I had to give my newly-adopted cat another home today. While she and Whisper had adapted to the point where at least they could be in proximity with each other without hissing or spitting - most of the time - she still didn't trust me enough to even make an attempt to pick her up, from arm height, while purring, just after being petted. Almost as soon as I touched her underside, she went to bite my hand, and then hissed.
That's not the sort of behavior I had in mind after a month, and it's still possible it was Whisper's presence that was setting her off, as that seemed to trigger similar reactions when I'd just pet her for the first couple weeks.
Fortunately, there were still other interested people that didn't have other pets, so I'm hoping she'll have a better time there. :) It would have been preferable to work out, but it does fit the pattern: most spur-of-the-moment decisions I make tend not to end well. Still, I'm glad I at least made the attempt.
That's not the sort of behavior I had in mind after a month, and it's still possible it was Whisper's presence that was setting her off, as that seemed to trigger similar reactions when I'd just pet her for the first couple weeks.
Fortunately, there were still other interested people that didn't have other pets, so I'm hoping she'll have a better time there. :) It would have been preferable to work out, but it does fit the pattern: most spur-of-the-moment decisions I make tend not to end well. Still, I'm glad I at least made the attempt.