Douglas Garland has been charged with first-degree murder in the deaths of Calgary residents Kathy and Alvin Liknes, as well as second-degree murder in the death of the couple's five-year-old grandson Nathan O'Brien.
Here is a timeline of the investigation so far.
The Amber Alert for the missing family has been discontinued. Police believe there is enough evidence to say they have been murdered, but their bodies have not been recovered.
- Amber alerts: When they're used and how they work
- 'Violent crime' happened at home
- Douglas Garland charged with murder of Nathan O'Brien, Kathy and Alvin Liknes
June 27-29: Alvin and Kathy Liknes hold an estate sale at their Parkhill home in southwest Calgary from 2 p.m. to 7 p.m. MT Friday and 8:30 a.m. to 4 p.m. MT Saturday and Sunday. The couple had recently bought a house in Edmonton and planned to clear out some things before moving. The O'Brien family comes over to help out with the sale throughout the weekend.
June 29, around noon: A neighbour sees Alvin Liknes at a nearby park playing with Nathan.
June 29, 10 p.m.: The estate sale is over and the O'Brien family heads home after a day of helping out. Nathan's mother, Jennifer O'Brien, leaves him with his grandparents for a sleepover.
June 30, 10 a.m.: Jennifer O'Brien returns to pick up Nathan but finds he and his grandparents are not in the house.
June 30, 5:15 p.m.: Police issue an Amber Alert for Nathan.
June 30: Police announce evidence in the house has led them to believe the disappearance of Nathan and his grandparents may be suspicious.
July 1 at 11 a.m.: Investigators say they have no "significant leads" about the whereabouts of the missing boy and his grandparents.
July 2 at 3 p.m.: Nathan's parents, Rod and Jennifer O'Brien, speak to media. They call Nathan a superhero and ask him to stay strong as the police search continues while making a tearful plea for his return. On advice of the police, the family has decided not to offer a cash reward at this time.
July 3 from 10 a.m.-10 p.m.: Investigators are at the Parkhill Community Centre to speak with anyone who attended the weekend estate sale. People are being asked to bring photos of what they bought to help investigators catalogue what was purchased and what remains in the house.
July 4 at 11 a.m.: Calgary police ask for the public's help in identifying a vehicle seen in the area the night Nathan and his grandparents disappeared. They say they want to speak with the driver, who they believe might have more information about their disappearances. For a description of the truck, click here.
July 4 at 2 p.m.: Calgary police find blood inside the Liknes residence, although it is not known whose it is, and confirm a violent incident took place. They say the victim would have been in medical distress.
July 5 at 10 a.m.: Police and a local search and rescue team begin a new ground search around the Likneses' home. This is the first time search and rescue teams have been called in on the case. Police say the search is a best practice five to seven days after a disappearance like this one.
July 5 at 5:40 p.m.: RCMP tactical teams and Calgary Police Service confirm search at a property in Airdrie, Alta., is linked to the search for Nathan and his grandparents.
July 5 at 6:30 p.m.: Police say a man from Airdrie property taken in for questioning. They have also taken a vehicle from the property that is similar in description to the one captured on CCTV images.
July 6 at 11:45 a.m.: Police announce the man taken in for questioning has been released. They said he remains a "person of interest" but police are not naming him or calling him a suspect.
July 6 at about 4 p.m.: CBC News confirms that Douglas Garland was released from questioning specifically in regards to the Nathan O'Brien disappearance, but remained in police custody in relation to the new charge of identity theft laid against him this weekend.
July 6 at about 6 p.m.: Investigators are still at the Airdrie property after ending a second search at another site nearby. They continued searching throughout the evening and into Monday.
July 7 at 11:15 a.m.: Douglas Garland made a brief appearance in court to face a charge of identity theft. Garland appeared via closed-circuit television. He was expressionless and leaned against a wall as the charge was discussed.
July 8 at about 9 a.m.: Investigators return to rural area north of Airdrie to resume search.
July 9 at about noon: Douglas Garland makes his second court appearance. His bail hearing is put over to Friday
July 9 at about 1 p.m.: Police expand search to Spyhill landfill in northwest Calgary.
July 10 at 10 a.m.: Police begin searching a second landfill in Calgary. Sources also tell CBC News that a business deal between Douglas Garland and Alvin Liknes had gone sour, leading to "bad blood" between the two. Police confirm they are investigating the business relationship between Garland and Liknes.
July 11: Douglas Garland is granted bail on the charge of identity theft, unrelated to the Nathan O'Brien case. His bail is set at $750 and he must report to a supervisor three times a week as well as once a week to police. He can't return to his parents' Airdrie property while it is under police investigation and must live in transitional housing while out on bail.
July 12: Search teams return to the Likneses' Parkhill home for another sweep of the property. Officers also return to the Spyhill landfill in northwest Calgary and continue their search of the Garland property in Airdrie.
July 13 at around 10:15 a.m.: Police announce their search of the Liknes home has officially ended following the previous day's final sweep of the property. It is being released back to the family, but police and RCMP are continuing to search the Airdrie acreage belonging to Douglas Garland's parents.
July 14 at around 10: 30 a.m.: CBC News learns that Douglas Garland — who had been named as a "person of interest" in the disappearance of five-year-old Nathan and his grandparents — is back in police custody. At a police press conference Monday afternoon, the Calgary police say they will be laying murder charges in the case. Police say they will not name the suspect until the charges are laid.
July 15 at around 7 a.m.: Douglas Garland is officially charged with first-degree murder in the deaths of Calgary residents Kathy and Alvin Liknes, as well as second-degree murder in the death of the couple's five-year-old grandson Nathan O'Brien. He is expected to appear in court on Wednesday.
July 16: Douglas Garland appeared in court on the murder charges he is facing. The case has been set over to Aug. 14. Meanwhile, a civilian search team that was looking to help police search rural areas near Airdrie was called off after online backlash, but some people decided to comb through ditches and fields in the area anyway.
July 20: Police conclude their search of the rural property near Airdrie where Douglas Garland lived. A spokesperson for the Calgary Police Service said police could still go back to the acreage if required.