July 1Police express interest in speaking to anyone who attended an estate sale at the Liknes home in the weekend leading up to the disappearances.
July 2Nathan's parents, Rod and Jennifer O'Brien, issue a nationally televised plea for their son's safe return.
July 3Police say footage from nearby closed-circuit televisions as well as tips from the public have moved the investigation along, but declined to provide details.
July 4Police confirm that a violent incident took place at the Liknes home, adding they recovered forensic evidence. They also released images of a green Ford pickup truck and said they believed the unidentified driver may have some information.
July 5Calgary police and RCMP descend on a property near Airdrie, Alta., just north of Calgary. Police recover the green Ford and take Douglas Garland in for questioning.
July 6Police enlist the help of a dog and a boat as they continue to comb the Airdrie property. Garland is released, but still publicly declared a person of interest.
July 7Douglas Garland appears in a Calgary court on an identity theft charge unrelated to the Liknes/O'Brien disappearance. He is held in police custody pending a bail review. Rod O'Brien tells reporters at the courthouse that there is a connection between Garland and the family, but would not elaborate.
July 8Calgary police say they have other leads to explore besides Garland and the Airdrie property, but offered no details.
July 9Police say they've expanded their search to the Spyhill Landfill northwest of Calgary. They also confirm that Garland's sister is in a relationship with a member of the Liknes family, and that the Airdrie property belongs to his parents.
July 10Police say they are probing business dealings in the Liknes family as part of their investigation. Officers did not provide details, but reports surfaced that Alvin Liknes recently had to close his gas exploration company after equipment was seized for unpaid taxes. Police said they had also begun searching other city landfills. Later that day, about 500 people attended a candlelight vigil at a community centre near the Liknes home.
July 11Garland is released from police custody on bail and given strict conditions, including instructions not to return to his parents' Airdrie farm where police were still conducting searches.
July 12Police return to the Liknes home to conduct more searches even as they continue to sweep the Airdrie property and local landfills.
July 13Police conclude searching the Liknes home but say the investigation continues at the Airdrie property and local landfills.
July 14Calgary police say they have made an arrest in the case and cancel the Amber Alert out on Nathan O'Brien. They say two charges of first-degree murder and one charge of second-degree murder are pending in the disappearance.