I believe that the household dogs have achieved thronghood. Pack doesn't seem like quite the right word--this implies some order among and ordering of beasts. I no longer have 2 individual identifiable dogs. With the addition of Casey, now when the three of them are on the move, it seems like multitudes. An amorphous mass of canininity. There might be three; there might be thirty; it's hard to tell. I suspect that they are moving in and out of alternate space-time continuums, so that it's impossible to count the true quantity in this here and this now.
With Jake, Tika, and Remington, we seldom achieved this oneness of togetherness; Rem was too stand-offish, Jake was too snappity around him, and Tika was too cautious of the Old Boy Network. There were rare occasions when they bounced off of each other with impunity, but this new threesome has achieved a Brownian activity level that's stunning in its complexity.
And I thought that Tika and Jake were way too noisy when greeting guests--Casey outdoes them with a shrieking, wavering yowl that sets one's ears to ringing. We're working on that, too... If they weren't all so damned cute, I'd become a cat person.