Right clicking on a baby animal with a milk bucket will show heart particles, meaning the baby will suspend its growth and will keep its cute littleness forever. And last but not least, you'll keep your empty bucket.

Right clicking a baby whose growth has been halted with a mushroom stew reverts this. It will show green particles, and the baby will continue to age as normal.

The items needed for suspending / resuming the growth can be customized in the config file.

Have fun!

Permissions:

• kittenforever.growth.stop: Allow the player to prevent a baby animal from aging by right clicking it with an item.
  
• kittenforever.growth.resume: Allow the player to resume a stopped animal growth by right clicking it with an item.
  
• kittenforever.growth.*: Includes the two above. Operators have this permission by default.