Missionaries Share Personal Journey About Mentally Ill Teen

A North Texas couple is on a crusade to help those in need share their very personal story about mental illness.

Dave and Lisa Stephenson took in a troubled teen who would later be accused of murder.

The uplifting photos in their home represent the chronicle of people who have been helped by the couple.

However, not all of the images have a happy resolution.

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Two years ago, they first met Thomas Johnson.

"The high school football coach saw us on the sideline, came up afterwards and said, 'Can y'all help one of my former players?'" recalled Dave Stephenson.

They thought their rural Farmersville home would be the perfect setting for a troubled South Dallas teen.

Thomas had been a standout football player at Texas A&M until the day he mysteriously walked away from campus and never returned.

In short order, he was arrested for car theft and jailed.

Even so, the Stephensons were more than willing to help.

"Without much of a background and never going into a jail and never knowing much about what to do, we just trusted God and said 'if this is where you want us and we'll to the best of our abilities try to help him in wherever he wants to go in life,'" said Dave Stephenson.

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His wife, Lisa, described Johnson as gentle, mild-mannered and polite, but says at times he would exhibit odd behavior.

"He would either stare into space and not be engaging or looking at us or he would just laugh about something when there was nothing funny," said Lisa Stephenson.

Looking back, Lisa Stephenson says she questions if that could have been a sign. What was Johnson thinking about?

She says about eight weeks in, Johnson abruptly left and returned home to Dallas.

His father said Johnson complained of hearing voices, so he took his son to a psychiatrist.

Johnson was diagnosed with schizophrenia.

Two months later, while under psychiatric care, the unimaginable happened.

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Johnson was accused in one of the most brutal murders in recent memory.

Police say Johnson used a machete to kill a perfect stranger, David Stevens, whose wife was so consumed by grief, that she then took her own life.

"He wasn't capable of that. The Thomas we knew was not capable of bludgeoning somebody like that," Dave Stephenson said.

The couple watched the news coverage on Oct. 12, 2015.

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Three days after the murder, the Stephensons visited Johnson in jail.

His mental state at that time still haunts them.

"He was just like he was sitting in our living room, 'how are you doing?' that he liked her haircut," said Dave Stephenson. "That's when we knew for certain that he was mentally ill."

"I mean, he was completely normal as if he didn't even remember that it had happened," Lisa Stephenson said.

But it did happen.

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His family says beneath the calm surface of his outward behavior, there was an escalating turbulence that resulted in tragedy.

"They could hear a voice telling them to do things or even a voice commenting on how they're behaving or even several voices conversing with each other," said Dr. Hicham Ibrahim, a psychiatrist with the O'Donnell Brain Institute at UT Southwestern Medical Center.

Ibrahim has been treating patients who have mental illnesses for nearly two decades.

Although he has no affiliation with Johnson's case, he tells NBC 5 that there are warning signs with a delusional patient and some can be easy to miss.

"Behaving inappropriately, reacting inappropriately, particularly change in how it used to be and how it is now. This is kind of the stuff that families can really point to," said Ibrahim.

He says increased awareness and proper treatment from the onset is key.

"They're really able to lead productive and fulfilling lives. We've seen patients who are treated well, have done really well in their lives," he said.

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After months of silence in jail, Johnson was transferred to a mental health facility in Vernon, Texas, and has been writing to his missionary family.

The letters give Dave and Lisa Stephenson hope and healing.

"That's really all we wanted was for him to get help. We don't expect him not to pay for what he did. That's not what it's about," Lisa Stephenson said. "We want him to have a shot at having as normal of a life as he can have. That may be in prison for the rest of his life, but at least he's not going to be in prison in his brain, as well," she said.

Johnson was declared mentally incompetent to stand trial for the murder.

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Doctors at UT Southwestern will soon be opening an early psychosis clinic to address the problem of not identifying people with schizophrenia early enough.

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