On the day that Olivia Robb's mother, Ellen Gregory Robb, was beaten to death in the family's Upper Merion home, police led the 12-year-old girl to where her father, Rafael, sat in a nearby ambulance.

"He told me not to worry, that everything would be fine," Olivia Robb testified Tuesday, speaking to jurors in the Montgomery County Court wrongful-death suit against her father. "No matter what I was told."

Instead, she lost both her parents. Within weeks, her father was behind bars for the killing.

Tuesday marked the first time that Olivia Robb, now 20, has spoken publicly about the case. Seated a few feet away from the father she had not seen for almost eight years, she did not glance at him once.

Slender, with long dark hair, Olivia Robb was emotional but poised as she described the anguish that followed the loss of the woman she called her best friend. She moved in with an uncle and was raised by her mother's relatives after the killing, but said she realized on her 13th birthday that she would miss her mother forever.

"I knew if my father made me cry or something, she would be there," she said. "I knew she would do whatever she had to do to protect me from anyone, including him."

Rafael Robb, 64, a former economics professor at the University of Pennsylvania, had no visible reaction to his daughter's testimony.

Robb is serving a five- to 10-year prison sentence after pleading guilty to manslaughter for bludgeoning his 49-year-old wife to death with a metal bar as she was wrapping presents just days before Christmas 2006. Her injuries were so gruesome that police first believed they had come from a shotgun blast.

The trial this week in Norristown will determine whether jurors will award Robb's remaining assets to his wife's estate and his daughter. The family is seeking punitive and compensatory damages.

Now a junior at the University of Vermont, Olivia Robb mourns the thought that her mother will never see her get engaged or offer advice on raising children.

"I think about all the moments she won't be there for," she said.

Robert Mongeluzzi, the attorney for Ellen Robb's family, called the lawsuit a way for Olivia Robb to attain financial independence from her father, who pays her college tuition and other bills. He estimated that Rafael Robb's assets and investments are "in the millions."

Until Tuesday, Olivia Robb said, she had not seen her father since the day of his 2007 arrest. She added that she would prefer never to see him again.

Their communications have revolved around her requests for him to pay various expenses, she said, and she added that he had used her reliance on him to manipulate her. In 2008 he sent her a letter asking her to send pictures and a copy of her report card in exchange for a holiday present. In 2012, when he first became eligible for parole, she said, he threatened to cut her off when she refused to write a letter supporting his release.

In an interview last year, Rafael Robb said he had established a fund for his daughter that is run by a trustee. He said he feared the girl's uncles would take the money if they were put in charge.

Gary Gregory, Ellen Robb's brother, told jurors Tuesday that the family had to take Robb to court to force him to pay child support after he was imprisoned. Gregory said he has told his niece that he would always take care of her, but that she feels pressured to maintain the relationship with Robb because he pays her bills.

Rafael Robb also testified Tuesday, telling jurors that he did not intend to kill his wife, but flew into a rage during a heated argument when she pushed him and caused him to fall. He panicked, he said, and clumsily staged a burglary scene to buy himself some time.

His only show of emotion came as he read from the apology he made to his daughter during his guilty plea. "I know she loved her mother," he said.

Mongeluzzi has argued that the crime was premeditated, pointing to testimony from a detective who said he believed Robb used a crowbar from his garage to kill his wife, instead of a metal exercise bar that Robb claimed he grabbed from the living room.

Olivia Robb was not in court for Robb's testimony, but she also disputed Robb's version of events.

"My father could lose his temper really rapidly," she said. "My mother didn't get angry, let alone violent."