Original: The first documented use of the Easter Bilby concept was in March 1968 in Rose-Marie Dusting's story called Billy The Aussie Easter Bilby. Rose-Marie Dusting, was a 9 year old child when she first wrote "Billy The Aussie Easter Bilby" 'in a small Queensland town called Richmond.
Simplified: Author Rose-Marie Dusting wrote a book in 1979 called Billy, the Aussie Easter Bilby.