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(CNN) -- Prosecutors on Thursday questioned George Anthony, the father of murder suspect Casey Anthony, about gas cans he reported missing around the time his 2-year-old granddaughter disappeared.

Casey Anthony's former boyfriend Anthony Lazzaro testified the day before that he had helped her break into the shed at her parents' home on June 23, 2008 -- one week after her little girl, Caylee Anthony, was last seen. According to testimony, however, neither Anthony's parents nor Lazzaro knew that the child was missing, as Anthony insisted that she was in the care of a nanny at the time.

Lazzaro said Casey Anthony called him and told him she had run out of gas. They got the gas cans, and Anthony put the gas in her car herself, he testified.

On June 24, George Anthony called police to report the break-in and report the gas cans missing. He testified that he saw his daughter later in the day and argued with her about the missing cans, because he had a hunch she had them, as she had taken the cans before.

Anthony said that when he went to get them out of his daughter's car, she bristled, brushed past him, quickly opened the trunk and retrieved the gas cans, throwing them down and telling him, "Here's your f---ing gas cans."

The gas cans are significant to the case because a piece of duct tape on them appears to be the same as that found on the mouth of Caylee's skeletal remains, which were found six months after the child went missing. The type of tape, prosecutor Linda Drane Burdick told jurors in her opening statement this week, is relatively rare.

"I'm probably the one who put that on" the gas can, George Anthony said, adding that at the time, after Caylee was reported missing, he and his wife were "running on fumes. ... I'm trying to do the best I can."

He said that when his daughter returned the gas cans to him, there was no tape on them. But he said a vent cap on one was gone, and he put the tape on "because I didn't want a gas smell in the shed or house."

George Anthony had several testy exchanges with defense attorney Jose Baez during his testimony, at one point telling him, "You're badgering me. You're trying to get me upset."

In addition to capital murder in Caylee's death, Casey Anthony, now 25, faces six other charges, including aggravated child abuse, aggravated manslaughter of a child and providing false information to authorities. If she is convicted by the jurors -- seven women and five men -- she could face the death penalty.

Anthony has pleaded not guilty and denies harming her daughter or having anything to do with her disappearance. Baez has said that once all the facts are known, it will become clear that his client is not guilty.

The Orlando trial, which comes after nearly three years of legal twists, turns and delays, has garnered interest nationwide. George Anthony testified Tuesday and was re-called to the stand Thursday for part of the morning session.

Also testifying Thursday was Ricardo Morales, who dated Anthony briefly in early 2008 before she met Lazzaro. Morales testified that the two continued their friendship after breaking up, to the point that Anthony stayed overnight at his house June 9 and 10, 2008. She brought Caylee with her, he said, and the three slept in his bed, with Anthony in the middle. He denied any sexual contact with Anthony while Caylee was in the bed.

He said that after June 10, he never saw Caylee again, but he saw Anthony on July 1 and again on July 15, when she picked him up at the airport after he had vacationed in Puerto Rico. At no time did she mention that her daughter was missing or had been kidnapped, he testified, and he saw no change in her demeanor.

She was "happy, smiling. She was asking us how our trip was," Morales said. "Just normal Casey."

Morales was one of numerous people, including Lazzaro, his roommates and other acquaintances, who said Anthony did not mention Caylee's disappearance between June 16, 2008, the day the little girl was last seen, until the evening of July 15, when Anthony's mother, Cindy, reported her missing to authorities. Each witness testified they saw nothing different in Anthony's demeanor and that she did not tell them her child was missing or had been kidnapped.

However, under cross-examination by Baez, those who saw Anthony and her daughter together testified that Caylee was well taken care of and that Anthony, at least to their knowledge, appeared to be a good mother.

Dante Salati, who testified that he went to high school with Anthony, testified that he saw genuine affection between her and Caylee. Asked by Baez whether he found it shocking that he wouldn't notice a change in her behavior after the little girl disappeared, Salati said yes.

Melissa England, an acquaintance who shopped and had dinner with Anthony on July 3, recalled her saying that she was thinking of leaving Orlando for a place with a better school system so Caylee "could get a better education."

England also testified that Anthony received a call and told some other friends that she had car trouble and couldn't go out with them. As she hung up, Anthony remarked, "Oh, my God, I'm such a good liar," England said. Anthony, listening to her testimony, shook her head.

England did recall that as she and Anthony were out with others that night, Anthony received several calls and became upset and cried, eventually saying she wanted to leave. England said her boyfriend told her Anthony was arguing with her brother, but Orange County Chief Judge Belvin Perry Jr. ordered the jurors not to consider that statement after Baez objected.

Anthony repeatedly visited at least two nightclubs during the month Caylee was missing and participated in a "hot body" contest at the Fusion Ultra Lounge. Two women who worked as "shot girls" selling alcoholic shots to club patrons there testified Wednesday that Anthony was a sort of overseer, telling them where to be and making sure they weren't harmed.

Lazzaro and his roommates said that when they asked where Caylee was, Anthony told them she was with her nanny, mentioning that the nanny was taking her to Universal Studios and to the beach.

In the early days of the investigation, Anthony said the nanny, who she said was named Zenaida Gonzalez and nicknamed "Zanny," had kidnapped Caylee. Authorities were never able to find the nanny but did track down a woman with that name who denied ever meeting Anthony and later sued her for defamation.

One friend of Anthony's, Matthew Crisp, testified that he met her for lunch on July 7 and asked about Caylee. Anthony told him "she was in Sanford on a playdate with one of her girlfriends who also had a child." Sanford is about 25 miles north of Orlando.

The Anthony's next-door neighbor, Brian Burner, testified Wednesday that he was doing yard work outside his house on June 18 when Casey Anthony approached him and asked to borrow a shovel "to dig up a bamboo root." She returned it about an hour later, he said.

George Anthony testified Thursday that he owns several shovels.

Prosecutors allege that Casey Anthony, after conducting searches regarding chloroform on her computer, used chloroform on her daughter, then put duct tape over her nose and mouth, suffocating her.

Baez, in his opening statement Tuesday, dropped bombshell allegations, telling jurors that Caylee was not murdered at all, but drowned in the Anthonys' pool on June 16. He said Anthony and her father panicked upon finding the child and kept it secret.

He explained Casey Anthony's behavior in the month Caylee was missing by alleging that she was sexually abused starting at age 8 by her father and that she had been schooled from a young age to "hide her pain."

In his earlier testimony, George Anthony denied ever sexually abusing his daughter or that he found Caylee dead in his pool.

HLN's "Nancy Grace" producers Philip Rosenbaum and Lee Alexander contributed to this report.

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