Photo: Shanann Watts /Facebook

Shanann Watts‘ friendNickole Atkinsonwas the first to realize something was wrong.
Atkinson had dropped Watts off at her home in Frederick, Colorado, early on Aug. 13 around 2 o’clock but didn’t hear from her again, Atkinsonsaid on Monday’sGood Morning America.
“She went inside, turned around and waved at me and shut the door,” she said of Watts, describing perhaps the last time anyone outside of Watts’ family saw her alive.
At some point after that,likely in her own home, Watts was allegedly murdered along with her two young daughters,4-year-old Bella and 3-year-old Celeste.
The suspect? Watts’ husband of nearly six years,Chris Watts, 34, who was arrested on Wednesday night.
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Atkinson said onGMAthat Shanann missed a doctor’s appointment that day.
What’s more, Atkinson said onGMA, security footage around the house “showed Chris leaving that morning and there was no movement in between those times of me dropping her [Shanann] off, Chris leaving and me coming back.”
“There was something seriously wrong,” she said.
Within days, authorities would reveal their suspicions: arresting Chris and accusing him of three counts of first-degree murder and tampering with a body. A motive has not been confirmed, though multiple friends have saidthere were marital issues.
On Thursday, the remains of Chris’ wife and girls were found,having apparently been concealed for days.
Shan’ann Watts (right) and her daughters.Shanann Watts /Facebook

Investigative experts who spoke with PEOPLE, but who are unconnected to the case, say that Chris appears to have beentrying to control a situationthat was spinning away from him.
Chris remains in custody and is scheduled to return to court to face formal charges on Tuesday.
His attorney did not respond to PEOPLE’s request for comment.
source: people.com