Prosecutors on the case of a 16-year-old suspect had to sift through a treasure trove of phone texts to prove things weren’t copasetic between the teen and his murdered parents.

In a Sneak Peak of Season 2, Episode 6 of Prosecuting Evil with Kelly Siegler, Texas authorities, including members of the Houston Police Department (H.P.D.) and Harris County Assistant District Attorney’s Ryan Trask and John Jordan, were tasked with building a case against teen murder suspect Antonio “A.J.” Armstrong Jr. The July 29, 2016, shooting deaths of his parents, Dawn and Antonio Armstrong Sr., in the bedroom of their Houston home were previously covered by Oxygen News and spanned seven years and three murder trials in total.

“Before the trial, there’s still evidence that can be gathered and collected to get the case even tighter and cleaner and stronger,” Siegler said in the recent clip. “In the weeks following the murder, H.P.D. begins putting together its case, along with the prosecutors, which includes the evidence they retrieved from the crime scene, as well as the alarm records and cell phone data.”

The text messages between the Armstrong family members

Some of the most damning evidence against Armstrong Jr. came in the form of text messages.

“Text messages showed that the family relationship, from the outside, it’s perceived as good, but it was volatile from within,” said Trask. “Through the text messages, we learned that there were issues between A.J. and his parents.”

In a text message dated April 23, 2016, as published by Prosecuting Evil, Dawn Armstrong asked her son if he obtained a “fake ID,” to which Armstrong Jr. responded: “no mam.”

A couple of weeks later, the mother accused the son of ceasing to share his location “AGAIN.” In another message, the teen said his phone died.

“There were events leading up to the night of the murders,” Trask continued. “He was using money on drugs, and more than anything, I think his mother was upset by the constant lying.”

Escalating tension between A.J. Armstrong Jr. and his parents

Troubles in the household mounted, and in the weeks leading up to the double homicide, Dawn Armstrong informed her son via text that she planned to disconnect his phone for his bad behavior, adding, “Enjoy your last few calls and texts.”

“You ignore every rule we set. You have shown us that you don’t give a [dash marks] about what we say!” the mother stated. “And it is time for us to deal with you! You are out of control. So disrespectful!”

In more messages published by Prosecuting Evil, the mother said she would only give Armstrong Jr. the money he needed, accusing him of “getting high” on her dime. She further called the situation “pathetic,” adding that she was “beyond disappointed.”

Text messages proved she attempted to ground the teen for his actions.

“You are immature and irresponsible and drink and smoke to show off which is stupid,” Mrs. Armstrong wrote in a May 25, 2016 text.

She also said, “All you do is drink and smoke and lie,” and that he was “flat out” dishonest about going to basketball practice. Other messages showed the teen claiming he was away playing football.

Prosecutors also discovered texts between Armstrong Jr. and his father, including one in which the father insisted his son “come clean.”

“AJ … you will understand what my wrath means … you have crossed so many lines,” the father stated. “You don’t deserve our kindness over a piece of tail. Your punishment will be severe, this is coming from me.”

Antonio Armstrong Sr. wrote he was “so disappointed” just weeks before he and his wife were found fatally shot in bed.

But would the texts amount to a murder conviction?

Find out in Prosecuting Evil with Kelly Sieger, airing Saturdays at 8/7c on Oxygen.