Catnapped!(1998)

Catnapped! is an animated film following a boy and his sister as they race to rescue their dog Papadoll from a band of anthropomorphic cats. The culprits whisk him away to Banapal Witt, a fantastical world built atop a colossal sleeping cat. Once there, the sun's strange magic transforms Papadoll into a towering monster, catching the attention of a spoiled princess with an unusual power: everything she touches becomes a balloon. She claims Papadoll as her new weapon and beloved pet, plotting to use him alongside a giant inflatable mouse to awaken and control the sleeping cat beneath the kingdom. What begins as a simple rescue mission becomes an adventure through a surreal landscape where the stakes grow stranger by the moment.