Laura Coward, 47, was standing outside the vehicle near Sundre, Alta., when she was arrested by RCMP on Tuesday afternoon. She has been charged with abducting the girl in violation of a court order, along with break and enter and theft involving a holiday trailer in the area.
Mounties have released few details in the case and are awaiting autopsy results to determine how Amber Lucius died. But officers said her death is considered suspicious and more charges could be laid.
The girl's father, Duane Lucius, alleged in a court affidavit when Coward filed for divorce in December 2007 that she wasn't the same after the birth of their daughter.
"She would anger easily and we would argue often," he said.
A few months earlier, they had an argument at dinner when she asked him to sit at the kitchen table and he insisted he wasn't hungry, said the document.
Coward "then said that I better sit at the table or she will cut Amber's neck. I went to the kitchen and saw (her) with a knife at Amber's neck," Lucius wrote.
"I sat at the table."
The girl was two at the time.
The couple separated one month later, in October 2007, after three years of marriage. They had lived on his parents' farm near Millet, south of Edmonton. Lucius, 44, did construction work and Coward had a job as an accountant.
She also had an older daughter from a previous marriage.
The pair initially shared joint custody of both girls, but the children primarily lived with Coward. The woman claimed in affidavits that her estranged husband often didn't take medication for his epilepsy and was prone to outbursts. She said she feared for her safety and the safety of the girls.
In several other affidavits, Lucius alleged his wife was using his epilepsy as an excuse to deny him visits with the children. He said he hadn't had a seizure since he was 18.
He also alleged that she refused to grant numerous court-ordered visits and "systematically denied and thwarted my access and relationship to my daughter." He provided a doctor's assessment that Coward was excessively possessive and protective of Amber.
But a letter on the court file from a daycare operator in Vauxhall, Alta., described Coward as an "excellent mother" and called Amber a "cheerful and friendly little girl."
Affidavits in the court file contain allegations not necessarily proven in court.
In June 2013, a judge named Lucius as Amber's primary caregiver and she moved back to the farm with him. Coward and the other child then moved to a rural property near Wetaskiwin to be closer to Amber.
RCMP were called several times to intervene in the couple's disputes.
In affidavits, Lucius wrote that during a visit last April, police got involved when Coward didn't return the girl to his home on time.
Last Thursday, she had another visit with their daughter and was to return the girl on Sunday night but didn't show, said the last affidavit on the couple's court file.
Lucius wrote that he then drove to Coward's home to pick up Amber, only to find other people moving in.
"The new tenants had advised me that (Coward) had moved out during the past week."
He said he called Coward's cell but got no answer. He then called her sister, who phoned other family and found out that Coward had dropped her oldest daughter off with family members, but no one knew where she and Amber were.
Lucius wrote that he believed Coward had fled the jurisdiction with his daughter and RCMP were helping him with the search.
Later that day, RCMP said a hang-up 911 call led them to the vehicle with the girl's body.
The force said Friday it was reviewing its conduct in the case and whether it should have issued an Amber Alert. An Amber Alert is an emergency system commonly used throughout North America when children are abducted. Police have the power to issue the alerts when children are believed to be in danger.
Coward is to appear in Didsbury court on Monday.
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