tardigrada

Once upon a time there was a mother tardigrade and her three little tardigrades: Gavin . . . Colin . . . and Doug. Gavin, Colin, and Doug live on a cozy little drop of H2O until one day, their mother tells them it???s time for them to leave home. In search for the perfect place to live, the three little tardigrades journey to an underwater ice cave, an erupting volcano, and even the moon! They can survive under extreme conditions, but can they avoid the Hairy Wolf Spider?.

After moving to a tiny house, a little girl is forbidden to get a pet until she introduces her parents to microscopic tardigrades, also called water bears.