'Squeaking' is a perfectly serviceable term for what he's doing. And don't expect Daine to start throwing out terms like 'echolocation' anytime soon.

Before settling back to let Peter take a look at the cat trees, Daine walks right up to them to get a closer look. They're covered in material that reminds her a bit of the throw rug in her room at the base, only thicker. She prods it thoughtfully, wondering if it's soft enough to be a safe landing site for a wee bat. It could work.

"Okay." Daine backs away from the cat tree. "Try 'looking' at that thing." It's more complex than the boulder, but still solid and unmoving.