Port Huron Police say a 7-year-old who was visiting from the Detroit area was an apparent drowning victim Monday evening.  Sgt. David Seghi says police were assisted by the Port Huron Fire Department, Saint Clair County Sheriff’s Department Dive team, and the U. S. Coast Guard.  The boy’s body was discovered by a jet ski operator in the water at the south end of the beach.  Seghi says several citizens helped in the search for the boy.  He was taken to a local hospital but efforts to revive him failed.