There's a chilling true story behind this happy family photo.

What looks like an ordinary photo of two smiling brothers is actually the prelude to a sinister crime.

Only hours after this happy family photo was taken, the man on the left Bart Whitaker had his brother Kevin (pictured on the right) and his mother Tricia (who took the photo) murdered after conspiring with his friends.

He also attempted to have his father killed, but failed.

Bart Whitaker is currently on death row in the Polunsky Unit, a notorious prison in Texas for the murders.

On December 10, 2003 the entire Whitaker family – Kent, his wife Tricia, and sons Bart and Kevin – were gunned down inside their home in Sugarland, Texas, by a masked man who had been waiting for them inside.

Kevin died instantly. Tricia died on the way to the hospital. Bart and Kent survived.

But in shocking twist made public not long after the deaths, it was revealed Bart was the mastermind behind the depraved attack.

He had convinced one friend to be the shooter and another to drive the getaway car. The whole thing was planned right down to the detail of Bart being shot in the arm – enough to make him look like a victim, without killing him.

Although Bart had been pretending to be the perfect son, he had been living a lie for years.

On the night of the shootings, the family had been out celebrating his college graduation. Only Bart had dropped out of college months before and had been partying hard ever since.

Whitaker claimed that mental illness, which was exacerbated by drug abuse, caused him to want his family eliminated.

But it's widely believed that the murders may have been an attempt to cover up these lies and that Bart was hoping to profit from the family's life insurance polices.

Still, his father stood by him and refused to believe that Bart had anything to do with the shooting.

Following a tip off that police would shortly arrest him for the murders, Bart fled to Mexico in 2004. He lived there for over a year under a false name, until he was found and arrested.

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At his trial in March 2007, prosecutors alleged that although it wasn't Bart Whitaker himself who had pulled the trigger, he was responsible for his mother and brother's murders because he masterminded the plan.

He was sentenced to death and is currently waiting on death row.

Bart's father immediately forgave him for murdering the rest of the family and has stood by him ever since. He even wrote a book called Murder By Family.

What's the creepiest story behind a family photo you've ever heard?