Chilling home security footage shows what teen did seconds after 'fatally shooting her mother'

Security footage recorded in the home of 14-year-old Carly Gregg shows what the teenager did in the moments after allegedly shooting her own mom.

Gregg, who is now 15, is currently on trial on charges relating to the death of her 40-year-old mom, Ashley Smylie, and shooting of her 39-year-old stepfather, Heath Smylie, earlier this year.

The events unfolded at the family’s home in Brandon, Mississippi, on March 19, when Gregg is accused of shooting Ashley and Heath after returning home from school.

Dr. Andrew Clark, a child and adolescent psychiatrist based in Cambridge, MA, spoke at the ongoing trial as an expert witness and diagnosed Carly with Bipolar II disorder.

On the day the shooting took place, Gregg allegedly woke up 'grumpy and irritable' and could not concentrate in school.

When she came home from school, she went into the backyard to let her dogs out, but after that Clark claimed her memory 'went blank'.

"Her memory came back as she was standing by the side of the road, having crawled out of a drainage pipe wet, and the police officer came by and picked her up," Clark said.

During a cross examination, prosecutor Michael Smith said it was 'convenient' that Gregg couldn't recall the period of time in which her mom died.

A psychiatrist claimed Gregg couldn't remember the shooting (Law&Crime Trials)

As part of the trial, the court saw footage filmed in Gregg's home after the alleged shooting took place, showing the teenager walking around the home.

In the video, Gregg could be seen sitting on a stool and texting on her phone.

Prosecutors in the case have claimed that Gregg text one of her friends after her mom's death and asked them to come over due to an 'emergency'.

According to Mississippi state prosecutor Kathryn White Newman, Gregg then answered the door to her friend by asking: “Are you squeamish around dead bodies?”

Newman claimed Gregg then led her friend to the bedroom, where her mom was lying dead on the floor.

Gregg has further been accused of sending a message to her stepfather from her mom's phone, which read: "Are you almost home, honey?"

Gregg could be seen texting after the alleged gunshots rang out (Law&Crime Trials)

On the stand, Heath said there was 'something about the phrasing' of the text which suggested to him that Gregg had written it.

He continued: "When I opened the door to the kitchen, the gun went off in my face before the door was even three to four inches wide open, and everything kind of went pretty fast from there. It was a blur."

Heath got into a struggle with Gregg and managed to get hold of the gun, but he initially believed Gregg had been scared of an intruder.

When he searched the home looking for the supposed intruder, he found Ashley's dead body with a bloody towel draped over her face.

Gregg attempted to run away after losing possession of the weapon, but she was arrested near the house soon after.

If you or someone you know is struggling or in crisis, help is available through Mental Health America. Call or text 988 to reach a 24-hour crisis center or you can webchat at 988lifeline.org. You can also reach the Crisis Text Line by texting MHA to 741741.