Police have scaled back their search for four-year-old Gus, who went missing six days ago from his family's remote homestead in South Australia. "Unfortunately, we are now having to scale back this search for Gus." A footprint found 500m from where missing boy Gus was last seen on his family's homestead. (South Australia Police)At least 50 people had been on site every day of the search and scoured through 25km of tough terrain around where Gus was last seen. (South Australia Police)Earlier this week, Gus' family said they were "devastated" and "deeply distressed" by his disappearance.