Scott Peterson's family still split over his guilt in murder of pregnant wife Laci Peterson

SAN FRANCISCO (KGO) -- One day after convicted murderer Scott Peterson was resentenced in a Redwood City courtroom, Peterson's half-sister says she still has no doubt that he's guilty of killing his pregnant wife Laci on Christmas Eve 2002.

"Seeing Scott in the courtroom, Scott still appears to be vacant and emotionless, even with a mask on," said Anne Bird, who shares the same mother with Peterson. "The behavior I witnessed was not of a grieving husband or father to be, but as a roving bachelor."

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In the weeks after Laci's disappearance, Scott Peterson sometimes stayed with Bird and her family at their Berkeley home.

"He went to the store and bought cocktail mix to make Sextinis for our babysitter at the time," said Bird. "The lack of interest in looking for Laci was very apparent."

Bird's comments are in stark contrast to those made by Peterson's sister-in-law.

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Laci Peterson, who was 8 months pregnant, went missing from her Modesto home in 2002.

Speaking to reporters outside Peterson's court hearing Wednesday, an emotional Janie Peterson says she and other family members will stand firmly behind Peterson in his appeal for a new trial.

"Scott Peterson is innocent," said Janie Peterson. "We're going to be back here in two months for a juror misconduct issue in Scott's 2004 trial, but that is not where the problem started. The problem started when Laci went missing and the Modesto police department did not follow up on sightings and evidence that she was alive."

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While his sister-in-law continues to proclaim Peterson's innocence after nearly two decades, Scott Peterson's sister is certain, her brother is guilty.

"I wish he would take just a fraction of pain away and just be honest," said Bird, who now lives outside of California.

Peterson will remain in the San Mateo County jail until his next court hearing in Redwood City next February.