HUNTSVILLE, Texas -- A Texas inmate was executed Wednesday for setting a fire that killed his 18-month-old daughter and her two young half-sisters at an East Texas home 15 years ago.

Raphael Holiday, 36, became the 13th convicted killer put to death this year in Texas, which carries out capital punishment more than any other state. It has accounted for half of all executions in the U.S. this year.

Asked by a warden whether he had a final statement, Holiday thanked his "supporters and loved ones."

"I love y'all," he said. "I want you to know I'm always going to be with you."

He thanked the warden. As the lethal dose of pentobarbital began, he took two deep breaths and appeared to yawn, his mouth remaining open as he wheezed several times. Then all movement stopped.

Nineteen minutes later, at 8:30 p.m., he was pronounced dead.

Holiday never addressed or looked at witnesses, including the children's grandfather and mother, his former common-law wife. The mother initially stood at the back of the death chamber witness area, watching from behind a corrections officer. About 10 minutes later, with Holiday motionless on the death chamber gurney, she walked toward a window to see him.

She and other relatives of the slain children declined to speak with reporters afterward.

The punishment was carried out after the U.S. Supreme Court rejected an appeal seeking to halt Holiday's punishment so new attorneys could be appointed to pursue additional unspecified appeals in his case. Austin-based lawyer Gretchen Sween argued that Holiday's court-appointed attorneys abandoned him after the justices in June refused to review his case.