'The Girl with the Cat' by Beverley Brenna; illustrated by Brooke Kerrigan

Nine-year-old Caroline visits the local art gallery and makes an extraordinary discovery.  It's a sculpture of a girl named Nina with a cat named Sammy on her lap, sitting in a rocking chair. There is no Do Not Touch sign like on the paintings - Caroline can actually push the chair back and forth, and pat Sammy. Then one day a sign is placed on the sculpture: Moving Soon.  Here begins the inspiring story of one girl's successful fight to save Saskatoon's famous Mendel Gallery sculpture, rallying an entire city to her side, proving to all that one person can really make a difference, even against soaring odds.  This is all a true story. Caroline was a real girl. And the sculpture is still in Saskatoon today. 
(Chapters.Indigo.ca)