A couple accused of beating to death the woman's 2-year-old girl appeared playful and happy at a picnic less than two weeks after the toddler's death, a witness testified Friday in the mother's trial.

Prosecutors planned to wrap up their case Friday against Kimberly Dawn Trenor, who's charged with capital murder in the death of Riley Ann Sawyers.

They have argued that Trenor and Royce Clyde Zeigler II are responsible for Riley's death, saying they beat her, dunked her head in cold bath water and threw her onto a tile floor, fracturing her skull during a daylong discipline session designed to teach her proper manners. Zeigler, who will be tried later, is also charged with capital murder in the girl's 2007 death.

Click here for photos of 'Baby Grace.'

Angelica Zenon worked with Zeigler at Emerson Process Management offices in Stafford, a suburb of Houston. She testified Friday that Trenor and Zeigler seemed happy and playful at the picnic.

"At any time, did these two people look like they were mourning the loss of a 2-year-old child?" Assistant Galveston County District Attorney Kayla Allen asked.

"No," Zenon answered, according to a report on the Houston Chronicle's Web site.

Zenon took photos at the picnic that showed Trenor smiling and playfully pulling Zeigler's baseball cap over his face. Allen showed the pictures to the jury Friday.

Zenon said she wasn't friends with Zeigler, even though she shared a cubicle with him. She said she heard him speak on the phone to Trenor as many as five times a day.

"Once, he screamed at her for refusing to allow his mother in the house," Zenon said. "It didn't feel like he had control over her, because he kept on and on."

Trenor's defense team has argued that Trenor was under Zeigler's control.

Click here for photos from the trial.

Documents introduced Thursday indicated Zeigler wrote a suicide note absolving Trenor in Riley's death. But the suicide note is contradicted by another letter in which he describes his plans to divorce her.

In a videotaped statement to police, Trenor admitted she whipped Riley with a belt and held her head underwater but that it was Zeigler who threw the toddler across the family room.

After Riley was killed, the couple bought a plastic container, partially filled it with cement, stuffed her beaten body inside and stored it in a shed before throwing the remains off a bridge and into Galveston Bay in September 2007, according to authorities.

Trenor and Zeigler met playing an online video game and married in June 2007 after Trenor moved with her daughter from Mentor, Ohio, a suburb of Cleveland, to Spring, a suburb north of Houston.

Riley was dubbed "Baby Grace" while investigators worked to identify her decomposed remains.

The toddler's identity was a mystery for weeks until Riley's paternal grandmother in Ohio, Sheryl Sawyers, saw an artist's sketch of the girl and told authorities in Texas she thought it was her granddaughter.

The call from Sheryl Sawyers led authorities to Zeigler and Trenor, who had invented a story that Riley had been taken away by child welfare officials in Ohio.

Trenor could receive an automatic sentence of life in prison without parole if convicted of capital murder. The jury could also convict her of a lesser charge.

Prosecutors declined to seek the death penalty against either her or Zeigler, 25, because they didn't think they could prove that the pair would be a future danger, a requirement for such a punishment.

Trenor and Zeigler are being held in the Galveston County Jail under bonds of $850,000 each.