Of course as far as everyone was concerned, it was normal...except for Jeff...he'd retain his memories, such as they were, of the prior reality.
It also meant he got to see the changes rapidly happening around him. First, he had shrunk, and before he'd gotten a chance to interpret that, he and his family had been transported into a cage.
In another few seconds, Jeff found himself falling to all fours. But the changes were still occurring.
He spotted Nibbles, his sister's former pet mouse, walk into the room, completely dressed. But, the mouse seemed to be wandering around aimlessly...as if he wasn't sure what he was doing.
Jeff approached mother and sister. "What are you two doing?" He asked, as they were both running. With each rotation of the wheel, they seemed to go faster, and more adept at running on all fours. "Exercising," they said, in unison. "Join us?" Their voices sounded a few octaves higher.
He looked over at his Dad, knawing on a piece of wood....his front teeth looking comically large on his face. He looked...well, happy...He was starting to look a bit pudgy around the midsection...he looked down...so was he...
Suddenly, he nearly jumped, because a giant mouse face was peeking in...it was Nibbles, looking closely at them. He was starting to look more purposeful...as if reality was changing to give him more of an agenda... "How are my humans today?" He said, suddenly, in a friendly sounding baritone.
"Can you understand me?" Jeff asked him, Jeff's voice sounding more and more high pitched. Apparently he couldn't...because there was no response. "Do you see this?" He asked his sister. She turned to him...a blank look on her face. She seemed to have even less awareness than she did a few seconds before.
Nibbles reached for the door to the cage and prepared to take Jeff out.