GALVESTON, Texas -- The mother of a man accused of killing his 2-year-old stepdaughter testified about his relationship with Riley Ann Sawyers, KPRC Local 2 reported Thursday.

Nellie Zeigler testified for several hours in the capital murder trial of Royce Clyde Zeigler II. He's accused of killing Riley Ann, whose unidentified body was nicknamed "Baby Grace" when found in a plastic container in Galveston Bay.

Nellie Zeigler said she and her husband were worried at first when they learned their son Royce had married a single mother with a 2-year-old child.

But she said that concern evaporated when Royce brought Kim Trenor and Riley Ann Sawyers home.

"Oh, he loved Kim. He loved her with all his heart. He was truly in love with her and Riley," Nellie Zeigler said.

She described her son as a caring, loving stepfather who quickly bonded with the toddler.

But she portrayed Trenor as a distant, detached mother who showed little emotion toward her daughter, and constantly clinged to Royce Zeigler.

"I thought at times it was like she could be jealous of their relationship," Nellie Zeigler said.

"This is the first time the jury is getting to hear some of the truth -- some of the story about who Royce is, not just people who come in and say bad things about him," said Dena Fister, a defense attorney.

About a month before Riley Ann was killed, Nellie Zeigler said she had found a bruise on the girl's leg. She confronted Trenor and her son and warned them.

"If you ever use a belt on her again, I'll use it on you," she said.

Riley Sawyers was beaten to death on July 25, 2007.

When Nellie Zeigler noticed the girl was missing, Trenor first told her Riley was visiting an uncle, then claimed she had been kidnapped by her grandmother in Ohio who Trenor said wanted custody.

She learned the truth in late November when FBI agents showed up at her house.

At one point on Thursday, the jury was shown the last pictures taken of Riley Ann before her death.

Nellie Zeigler cried as she saw them. Royce Zeigler did not look. He covered his eyes with his hand.

The defense is using Nellie Zeigler's testimony to rebut the prosecution's portrait of Zeigler as an antisocial loner who had little use for the toddler, and who was obsessed with disciplining her.

The defense rested its case Thursday afternoon. Closing arguments will be heard on Friday morning.

Trenor is already serving a life sentence for capital murder in her daughter's death.

Prosecutors say Riley died after a violent discipline session in July 2007. A fisherman found her remains three months later.

If convicted of capital murder, Zeigler faces life in prison without parole.