Police won't disclose the name of the alleged victim or of the 19-year-old accused, who has yet to appear in court.
But Parsons' father, Glen Canning, says the charges relate to online threats made against him last year.
Canning also says the accused is one of two teens facing child pornography-related charges in connection with his daughter's case.
RCMP spokesman Cpl. Scott MacRae says police began investigating last Aug. 2 after receiving a complaint from a 49-year-old man.
Police say a 19-year-old man was arrested Thursday and is due in court May 20 on charges including uttering death threats and criminal harassment.
Police initially did not lay charges, but reopened their investigation and have charged two teens with child pornography-related offences. That case is due back in court later this month.
Parsons' death made international headlines and prompted new laws cracking down on cyberbullying.
Earlier this month more than 150 people marched in Cole Harbour, N.S., to mark the first anniversary of her death.
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