A man facing a possible death sentence in the 2008 slaying of his ex-girlfriend and her 3-year-old son at a BREC park near Zachary has until Aug. 25 to plead guilty in return for a life sentence, a prosecutor said Thursday.

East Baton Rouge Parish Assistant District Attorney Darwin Miller told Dominique Dantoni Smith and his attorneys that the state’s offer will be removed from the table once that deadline passes.

“He’s got until that day,’’ Miller said during a status hearing before state District Judge Tony Marabella.

“We are not in a position to either accept or reject’’ the offer today, Richard Goorley, one of Smith’s attorneys, responded.

Smith’s girlfriend, Trendall Lashel Matthews, accepted the state’s offer and pleaded guilty Monday to two counts of first-degree murder and two counts of attempted first-degree murder in exchange for a life sentence.

Prosecutors were seeking the death penalty against Matthews, 25, of Jackson, as well.

She was set to stand trial next month.

Smith, 30, of Wilson, does not have a trial date.

Smith is accused in the killing of Jessica Johnson Palmer, 23, of Baker, and Juan Palmer Jr., 3, at Doyle’s Bayou Park on Pride-Port Hudson Road on May 4, 2008.

Smith and Palmer were once romantically involved and had a child together.

Matthews and Palmer are cousins.

Smith also is charged with the attempted first-degree murder of two of Palmer’s children: Lindsay Paige Johnson, who was 4 years old at the time, and Robbyn Palmer, who was 6 months old.

Lindsay Johnson, whose throat was slit, and Robbyn Palmer were left overnight in the park for dead.

Matthews, who had denied being at the park with Smith, admitted Monday that she was holding Juan Palmer Jr. and Lindsay Johnson when Smith cut them.

Matthews also said Smith killed Jessica Palmer, but that she held her down while he cut her.

East Baton Rouge Parish sheriff’s detectives have testified previously that Smith implicated himself and Matthews in the attacks.

Smith told detectives he and Matthews bought a baseball bat and lighter fluid before meeting Palmer and her children at the park, according to an arrest affidavit.

Smith said he and Palmer went for a walk, during which he grabbed her hands while Matthews attacked her, the affidavit says.

Smith said he and Matthews purchased new clothes at an area store and used the lighter fluid to burn the clothes they were wearing, the affidavit states.