SARASOTA COUNTY, Fla. (WFLA) – During a news conference Tuesday, Teton County coroner Dr. Brent Blue estimated Gabby Petito’s time of death to be three to four weeks before her remains were found on Sept. 19. The coroner pointed out we may never know exactly when the 22-year-old was killed.

Here’s what we know happened within that three to four week estimated timeframe.

August 27 was the last day Gabby was seen in public. Multiple witnesses confirm seeing Petito at the Wyoming restaurant, Merry Piglets.

About an hour away from that restaurant, her van was also captured on camera that day by Spring Hill travel bloggers at the Spread Creek Dispersed Camping area which is in the proximity of where authorities later discovered her remains.

According to a search warrant document released to 8 On Your Side last month, Petito’s mother Nichole Schmidt received an odd text from Gabby’s phone.

Three days later on Aug. 30, Schmidt receives a final text from her daughter’s phone.

This first court document released in relation to the disappearance of Petito reveals her fiancé Brian Laundrie returned to North Port the morning of Sept. 1. Per the license plate reader at the Sumter Boulevard exit off I-75, Petito’s white Ford camper van entered the city at 10:26 a.m.

When the federal warrant for Laundrie’s arrest was announced on Sept. 23, the FBI indicated the indictment was related to Laundrie’s activities following Petito’s death. The indictment document itself says the fraudulent use of Petito’s debit card happened on or between Aug. 30 and Sept. 1.

8 On Your Side spoke with Dr. Shelly Wagers who is an assistant professor of criminology at the University of South Florida. She is also a former law enforcement officer. Dr. Wagers explained why narrowing the time of death is critical in this investigation.

‘By narrowing it within a smaller window, it allows the police officers or the investigators to narrow down the suspect pool. In that, who are all the possible people that could have had contact with Gabby Petito within that smaller window and as that window is smaller, you can generally narrow it down to just a couple of people then you can move forward in the investigation in that capacity,” explained Dr. Wagers.

Officials with the FBI declined to comment on the autopsy findings released this week citing the ongoing investigation.