The Arizona Democrat, who is recovering from a bullet wound to the head that nearly took her life, learned last month that the six victims who died included her aide Gabe Zimmerman, her friend U.S. District Judge John Roll and a 9-year-old girl, Christina-Taylor Green.
The full extent of the mass shooting had been kept from her to allow her time to heal to the point where she could understand and process the information, the newspaper said.
Giffords spokesman C.J. Karamargin confirmed Friday the congresswoman was told the names of the dead in late July, just days before she made her first return to Capitol Hill to cast a vote to raise the federal debt ceiling.
"She was deeply saddened by it," Karamargin told the Republic on his last day on her staff before starting a new job at Pima Community College.
The Republic had reported in April Giffords initially learned about the shooting by peering over her husband's shoulder as he read aloud from a news story about her, but the specifics were kept from her.
Giffords talked briefly by phone with Zimmerman's father Ross Aug. 7. He told the Republic Giffords "still has some trouble with language, but there is no question that she can get her point across and her comprehension is 100 percent."
"It was Gabrielle -- it was nice to talk to her," the elder Zimmerman said.