As the afternoon went on, Derrick and Julies minds began to alter more with their young cub bodies. They began to think of themselves as each other and forget all the things they'd known as grown kids. The desire to play, wrestle, and hunt became predominant and their gender roles solidified. Eventually, they had no memory of being anything other than their new gender and their age.
"Rrrr....I feel great Julie," the former Julie purred.
"Yeah me too," Derrik replied, licking her long paw feet. They'd wandered away from the other cubs now, hearing the deeper roars of their parents. "Sounds like mom and dad are making us a new brother or sister..."