WHO IS WILLIAM CALLAGHAN?
*14 years old.
*Has non-verbal autism, taps his chest to communicate.
WHAT HAPPENED TO HIM?
*William went missing about 2.20pm on Monday after walking ahead of his family as they trekked the Mount Disappointment summit, about 60km north of Melbourne.
*Was found alive and conscious by a volunteer about lunchtime on Wednesday.
*Had never before spent a night outside by himself or been camping.
*Was last seen wearing only a blue hoodie and track pants.
*On Monday night, the temperature dipped toward zero degrees. Tuesday night was about 5C.
WHAT DID THE SEARCH INVOLVE?
*More than 500 people have been looking for William, including members of the public, Victoria Police, Victoria's State Emergency Service, Bush Search and Rescue Victoria and the Country Fire Authority.
*Thomas the Tank Engine tune was blasted over sound systems to try and draw him out and food left out for him to find.
*Airwing used thermal imaging to try and find William in the dense bushland.