In a statement read by her grown daughter, Gina Peterson, who lived with accused shooter Esteban Santiago, also expressed her "deepest condolences to the innocent people who lost their lives and/or were injured."
"My warmest sincerities go out to the families, friends," Robyn Peterson told CNN affiliate KTUU
on behalf of "my mother, brother and sisters."
Robyn Peterson, who identified herself as Gina Peterson's oldest daughter, said she did not know Santiago well.
"But I never felt like, you know, this was going to happen," she said. "No one knew this was going to happen, and we're just completely ... It's a tragedy, for sure. Taken aback by it, 100 percent."
Authorities say Santiago, 26, has confessed to the Friday mass shooting at Fort Lauderdale-Hollywood International Airport. He faces three federal charges
, including two counts that carry the possibility of the death penalty.
Asked whether her mother feared Santiago, Peterson declined to comment.
Court records obtained by CNN show Santiago was arrested in January 2016 and charged with assault and criminal mischief after an argument with his girlfriend in Anchorage, Alaska.
At the time, Santiago allegedly yelled at his girlfriend while she was in the bathroom, according to the complaint. Then he broke down the bathroom door.
The woman told investigators Santiago strangled her and struck her in the side of the head, the complaint said. Santiago left before police arrived.
Santiago pleaded no contest to criminal mischief and assault charges, a prosecutor said. He was due back in court this March.
Santiago's aunt told CNN her nephew had been living with his girlfriend and their child before Friday's massacre.
According to law enforcement officials, Santiago in November brought his newborn child and a loaded pistol with him to visit the FBI's Anchorage office
. He allegedly told authorities that an intelligence agency was telling him to watch ISIS videos, the officials said. The child was in the care of the FBI until his mother came to get him, an agency spokeswoman said.
Local police say they kept the gun until Santiago retrieved it last month. The same gun was used in last week's attack, law enforcement sources said.
Alaska court records show Robyn Peterson's father, William Peterson, filed for divorce in 2014 from Gina Peterson, with whom he had four children, KTUU reports.