The mother of a toddler who died after his father left him all day in a hot car told police that -- like her husband -- she researched child deaths in hot cars, according to new documents from police.
The documents were released the day after the funeral for 22-month-old Cooper Harris was held in University Church of Christ in Tuscaloosa, Ala.
Cooper's father Justin Harris is accused of the toddler's murder and is being held without bail in Cobb County, Ga. According to police warrants released Saturday, Harris, 33, told police he searched child deaths inside vehicles and "what temperature it needs to be for that to occur" because he "was fearful that this could happen."
Video: Father Charged With Son's Murder
According to newly released warrants, Harris' wife Leanna Harris told police she did the same thing.
"Leanna Harris, the child's mother was also questioned regarding the incident and made similar statements regarding researching in car deaths and how it occurs," read the warrant.
Leanna Harris has not been taken into custody or listed as a suspect by police.
She and her husband spoke to the public for the first time when they addressed mourners Saturday at Cooper's funeral, according to ABC News affiliate WSB-TV in Atlanta. Harris called from the Cobb County Jail and spoke via speaker phone, thanking those who have supported him, according to WSB-TV.
Leanna Harris also spoke to mourners and called her husband a "great father," according to WSB-TV.
Justin Harris has pleaded not guilty to the charges.
According to police, Harris left Cooper in his car when he went to work around 9:30 am June 18. Harris told police he forgot to drop Cooper off at daycare after he had breakfast at Chik-Fil-A restaurant and did not notice his son was in the backseat until around 4:30 p.m. when he was driving to drinks with friends.
When he noticed his son in the back seat, he said he immediately stopped the car and attempted to perform CPR. Witnesses told police Harris was yelling "Oh my God what have I done" as he pulled his son out of the car.
Cooper was pronounced dead after emergency personnel arrived.
Harris was arrested after police executed a search warrant in his office and home. According to The Associated Press, police also determined that Harris returned to his car at some point during the day and put something inside.
Police served warrants after Cooper's death to search computers or electronics for signs of evidence in the alleged crime.
The Associated Press and ABC News' Katherine Faulders contributed to this article.