The discovery comes on the first day of the fresh search for evidence linked to the boy’s 2014 disappearance.
Although it is too early for police to determine whether the toy belonged to William, it may be used to search for new leads.
The new search will take four weeks and span three square kilometres of bushland in the NSW mid-north coast town of Kendall, where the child was last seen in his foster grandmother’s front yard on September 12, 2014.
The search coincides with William’s seventh birthday, which is in two weeks time.
The group searching the area, which includes experts, riot officers, sniffer dogs and emergency service workers, already covered a large area of land today, finding multiple bags of potential evidence.