By JUAN A. LOZANO and MICHAEL GRACZYK
Associated Press

HUNTSVILLE, Texas (AP) - A Texas inmate who says he's intellectually disabled is facing execution for fatally stabbing his two stepsons during a 2007 attack in their North Texas home that also killed his wife.

Robert Sparks is set to receive a lethal injection Wednesday evening for the slayings of 9-year-old Harold Sublet and 10-year-old Raekwon Agnew in their Dallas home.

Appeals by Sparks' attorneys to stop his execution on claims he's intellectually disabled have been turned down by lower courts.

Sparks' remaining appeal, before the U.S. Supreme Court, focuses on other legal issues, including whether his jury was influenced by a bailiff who wore a tie showing his support of the death penalty.

If the execution happens, it would be the 16th in the U.S. and the seventh in Texas this year.

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