Okay, now they're stepping like they're practicing for the "Be Prepared" song from the Lion King! Do they even wanna be apart at this point?!

... Well, yes and no, actually. Kai's theory is that conjoined siblings, having been together their entire lives, develop a psychological attachment to each other where, if they were to be split, they'd naturally be drawn to each other like a moth to flame.

It's possible that the urge can be treated with psychiatric assistance, but it was important to the test that the three raw-dog the experience, to not interfere with the results.

The Astras are probably like this too, but it's hard to tell since they fly into a panic when they are separated for even a nanosecond...

Also yes, Zak and Wheezie are aquainted with the triplets. Yes Zak and Rex have some bad blood between them.