Now, however, they aren't so sure that time line is accurate.
"The family has not been forthcoming," said Senior DPS Trooper Sparky Dean. "Their discernment of the truth continues to change. It's very frustrating."
Hailey's mother's boyfriend, Shawn Adkins, claims to be the last person to see the teen before she vanished from her home in Colorado City, a small town of 4,000, located halfway between Abilene and Midland. Adkins said on the afternoon of Monday, Dec. 27, Hailey told him she was going to stop by her dad's house before staying at a friend's home that evening. She left the home and hasn't been spotted since.
"At this point, we aren't positive if she went missing (on that) Sunday, Monday, or even Tuesday," Dean said during a news conference on Jan. 9.
One thing that is for sure – Hailey's mother Billie Dunn reported her missing Tuesday, Dec. 28. Thirteen days into the investigation, authorities say they have yet to discover evidence of foul play, and it appears Hailey is hiding and doesn't want to be found.
"I'm confident we'll find Hailey," said Dean. "I don't think Hailey wants to be found. I believe she's hiding. She's probably scared at this point. We're going to find her."
Dean tells KTAB News Billie Dunn was asked additional questions over the weekend by investigators. Billie Dunn also told KTAB's Tiffany Tatro that she was asked to take another polygraph test. She went on to say she's not sure if she'll take it because she's frustrated with the system. Billie Dunn claims both she and her boyfriend Shawn Adkins failed their polygraph tests last week. Investigators say they never revealed results of the testing to Dunn or Adkins.
Dean told the media that 12 agencies are involved in the search for Hailey. After canvassing Hailey's Colorado City neighborhood and doing a thorough search of the town of Dunn over the weekend, authorities are now primarily following up on leads.
The latest lead to surface involves two girls investigators are asking to come forward who might have key information regarding Hailey's whereabouts. Over the weekend, a new witness told authorities that he or she spotted Hailey walking with two other girls in the 200 block of Manuel Street in Colorado City. The witness couldn't recall whether she spotted the trio on Sunday, December 26 or Monday, December 27. The witness recalls seeing the girls between 1 p.m. and 3 p.m.
"These girls are not suspects," said Senior DPS Trooper Sparky Dean. "These girls may not realize that they have some very valuable information."
Meanwhile, volunteers continue to organize searches in hopes of finding Hailey hiding in rural, wooded areas. According to the "Help Find Hailey Dunn" Facebook page, a search was planned for early Monday morning in Coahoma. People interested in searching planned to meet at the volunteer fire department.
On Friday, Saturday, and Sunday, hundreds of people took part in grassroots searches in and around Colorado City. Law enforcement says they're not directly involved with these searches and they appreciate the efforts of the volunteers.
At last check, the elite search group Texas Equusearch was one standby to come assist with the investigation. TES says they were requested to come help by the Dunn family. On Friday, TES told KTAB News they were speaking with authorities about how they might be able to help out.