Texas set to execute Travis James Mullis for the murder of his infant son. What to know.

This story includes graphic descriptions of crimes committed against an infant.

Texas is set to execute Travis James Mullis on Tuesday in the murder of his infant son Alijah, described by his grandmother is a "very precious" baby.

Mullis, 38, is set to to die by lethal injection about 16 years after he molested and killed 3-month-old Alijah before abandoning him in a secluded area of Galveston’s Seawall, a popular tourist destination just south of Houston.

If the execution proceeds as scheduled, Mullis will be the fourth person executed in the state this year and the 15th or 16th in the nation, depending on whether he's declared dead before or after Marcellus Williams, another inmate set for execution in Missouri on the same day.

Mullis’ execution will also be one of five scheduled across the nation between Sept. 20 and Sept. 26, with Freddie Owens the first to be killed on Friday in South Carolina, USA TODAY reported.

Here’s what you need to know about Travis Mullis’ execution.

What was Travis Mullis convicted of?

Mullis was convicted in the death of his infant son, who was choked, sexually abused, stomped to death and discarded a secluded area of the seawall on Jan. 29, 2008. He got rid of all the evidence, including the car seat and Alijah’s body, before he fled the state.

Mullis turned himself in and confessed to killing Alijah four days later, telling police in Philadelphia that he did it after hitting his “breaking point” because he couldn’t get the baby to stop crying.

He was convicted of capital murder on March 11, 2011 and sentence to death 10 days later.

Mullis has never denied killing his son, but has waffled about contesting his death sentence for over a decade. He lost the ability to appeal in state court years ago, but sought a reprieve from federal court with new counsel in July 2013.

Mullis’ attorneys have argued that his conviction was the result of ineffective lawyering, court error and constitutional errors made at trail.  A federal court eventually dismissed Mullis’ request to throw out the death sentence, and an appeals court affirmed the dismissal in June 2023.

Peter Walker, one of Mullis' defense attorneys, told the Houston Chronicle in May that he thinks the decision to move forward with Mullis' execution without a review of the constitutionality of his sentence is a “systemic failure.”

Who is Travis Mullis?

Mullis grew up with relatives in a small town in Maryland, following the death of his mother when he was just an infant.

He spent his early childhood and most of his teens, receiving intermittent mental health treatment and medication for behavioral issues as a result of sexual abuse by a family member. Mullis stayed with his aunt until he turned 18, which is when he was told that he either needed to take his medications or get out, according to court documents.

He decided to leave.

Mullis moved to Texas, living with a friend who said they could take him in temporarily. Then, he lived in and around Houston for a while, staying with anyone who would take him in. Mullis began a relationship with Caren Kohberger and the couple had Alijah.

The young family, which was facing financial hardship, moved into a trailer with one of Mullis’ friends and her family in Alvin in metro Houston, court records show.

Who was Travis Mullis' son?

Alijah, according to his grandmother Carolyn Entriken, was the most “extraordinarily beautiful” baby she had ever laid her eyes on, USA TODAY reported.

“He had steel blue eyes, cute little reddish hair," Entriken told the court, according to a March 2011 transcript obtained by USA TODAY. "I know all babies are beautiful ... He just was very precious."

Entriken did get a chance to visit her grandson in Texas before he was killed, visiting the area in December 2007 from her home in northern New Jersey.

Mullis, according to Entriken, seemed “very loving and caring" during the first vist.

“He had his arms around my daughter. They were being playful. He looked very loving,” Entriken said. “They looked like a young family out on an outing.”

Entriken, who died in 2022, said she had planned to visit again soon.

“I wanted to come back and see Alijah,” according to Entriken. “I didn't want too much time to go by where he was growing up without my seeing him.”

When and where will Travis Mullis be executed?

Mullis is set to be executed by lethal injection at the Texas State Prison in Huntsville, about 70 miles north of Houston, anytime after 6 p.m. CT on Tuesday, Sept. 24.

The Texas Department of Criminal justice plans to use a “single drug protocol of pentobarbital” to carry out Mullis’ death sentence, a corrections spokesperson told USA TODAY on Thursday.

What will Travis Mullis’ last meal be?

Mullis will choose his last meal from a menu “available to all inmates at the Huntsville Unit” since condemned inmates in Texas no longer make last meal requests.

Who will witness Travis Mullis’ execution?

It was not immediately clear how many, or if any of Mullis’ relatives, planned to attend the execution.

Reporters from a handful of media outlets will be in attendance, including:

• The Associated Press

• The Huntsville Item

• Houston Chronicle

• KPRC Houston

When is the nation’s next execution?

Mullis’ execution is the second of five scheduled across the nation in a six-day period. Mullis’ execution follows that of Freddie Owens, who was the first person executed in South Carolina in more than a decade on Friday.

Missouri also plans to execute Marcellus Williams on Tuesday in the death of 1998 fatal stabbing of former reporter Leisha Gayle despite prosecutors and victim family members arguing that he should be spared because he could very well be innocent.

There are two more back-to-back executions scheduled on Thursday.

Alabama is set to use nitrogen gas to execute Alan Eugene Miller in the shooting deaths of three co-workers in 1999 despite evidence of his mental illness and a witness to the state's previous nitrogen gas execution in January who described the method as "horrific."

Also Thursday, Oklahoma is set to execute Emmanuel Littlejohn in the death of a convenience store clerk in 1992 despite his arguments that he wasn't the shooter.

If all five executions proceed, the U.S. will have executed 18 death row inmates this year. Another six are scheduled, and more could be added to the calendar.

Contributing: Amanda Lee Myers

This article originally appeared on USA TODAY: Travis James Mullis to be executed in Texas on Tuesday. What to know.