Tributes were paid to teenager Michael Brooks at a memorial event on Saturday 10.
Hundreds attended the candlelit celebration of his life in Avenham Park, where Michael was last seen.
His body was found in the River Ribble at Preston docks on February 6. Michael was a former pupil of Preston College.
Speaking to the Lancashire Evening Post, Michael’s mother, Joanne Brooks, said: “The turnout on Saturday was much appreciated. It was a lovely tribute which is a great comfort to the family and will stay with me forever.”
Lancashire Constabulary confirmed that a post mortem examination will take place to establish the cause of death.
A Police spokesperson said: “At this time it is not being treated as suspicious.”
A date for his funeral is yet to be set.