David Perry 
Hippity Hoppity the White Kangaroo [EPUB ebook] 
Poison Leaves

This is an educational childrens story for children from five to twelve years of age.
It is about a white kangaroo who was rescued as a joey by a mother and daughter in a suburban home. But the white kangaroo, Hippity Hoppity, got too big, so they decided to let him go in the bush.
Hippity Hoppity was unsure what to eat, and when two little girls fed him some branches off a tree, he passed out. Cleverly, the little girls made a sled from their backpacks and dragged him to a doctor. The doctor managed to dislodge the leaves and drove Hippity Hoppity and the exhausted girls back to where the girls first found him.
When they arrived, they noticed two red kangaroos eating from the same tree. They must have seen the girls feeding Hippity Hoppity with its branches and tried them for themselves.
This is the lesson from this story: do not feed wild animals.