The boy was camping with his family in Drumnadrochit when a man approached the child in his tent at Loch Ness Bay Campsite
John Bell, 44, was charged over the assault at the Loch Ness Bay campsite near Drumnadrochit.
The boy was camping with his family in Drumnadrochit when a man approached the child in his tent at Loch Ness Bay Campsite between midnight and 1am on Thursday July 31.
His father, who was sleeping in an adjacent tent, saw the suspect leave his tent, at which point he asked the man what he was doing.
He was remanded into custody at HMP Inverness and made no plea during his appearance at court in September.
It is understood that he died in his cell on Saturday.
A Scottish Prison Service spokesperson said: "Every death, whether in prison custody or in our communities, is a tragedy for all those who knew and supported the individual.
"Following the death of someone in our care, Police Scotland are advised and the matter reported to the Procurator Fiscal. Fatal Accident Inquiries are held in due course.
"There do not appear to be any suspicious circumstances, and a report will be submitted to the Procurator Fiscal."
