She said Bauman also suffered burns on his back and an injury to his right eye. She said he was stable and resting, responsive, but not fully aware of his surroundings or the extent of his injuries.
He will need further surgery on his legs in the next few days, she said.
She and Bauman's father, Jeffrey, grew up in Oaklyn, Camden County. Csilla Bauman graduated from Paul VI High School. They met and married others and, after becoming divorced, connected and wed.
For a time they lived in the Philadelphia neighborhood of East Falls, where Jeff, who lived with his mother in New England, would visit as a kindergarten and first-grade student. The couple moved to New England to be closer to him, and now reside in New Hampshire.
Jeff Bauman grew up in Chelmsford, Mass. He maintains close relationships with an aunt and uncle in Villanova and with other family members in South Jersey.
On Facebook, his father thanked friends and family for their thoughts and prayers.
"Unfortunately my son was just in the wrong place at the wrong time," he wrote. "He went back into surgery [Monday] night at midnight for exploratory due to fluid in his abdomen. He came out at 2:30 and doctors informed us he was doing better."
Boston Medical Center officials said they received 23 patients, ages 5 to 78, of whom 19 remain hospitalized, 10 in critical condition. The majority will require further surgery.
The injuries to Bauman rocked friends here.
"Csilla and I have been friends since we were teenagers," said Mary Charno, of East Norriton, an advertising agent who grew up in Audubon.
Jeff Bauman has always been a big hockey fan, she said. About three years ago the families met for a game in North Jersey. On Monday evening, Csilla Bauman called from the car on the way to the hospital. "She said to me, 'Please say prayers.' "
Csilla Bauman said Jeff had gone to the marathon - his first - to cheer on his girlfriend, who was running the race. The family learned he had been hurt from Facebook, she said, when her daughter's boyfriend recognized Jeff in a photo.
A rush to Boston followed. Bauman's mother, with whom he lived growing up, resides in Massachusetts.
"We heard the bad news about his legs five minutes before reaching the hospital," Csilla Bauman said. "We were able to see him immediately, held his hand, and talked to him. They let all of us in. He has a big family."
Many aunts and uncles have arrived at the hospital, and other relatives from the Philadelphia area were on their way, she said.
"We almost lost him," she said, struggling to maintain her composure.
Bauman is athletic, she said, a hockey player through middle school and a baseball player in high school who continued to play basketball in recreational leagues until recently. A big fan of the Red Sox and Celtics, he works at Costco, and in his off hours loves to play guitar and sing.
She has not yet looked at the uncropped photo, which shows an ashen, dirt- and blood-smeared Bauman being rushed from the scene.
"My son could be gone right now," Csilla Bauman said.
She also was thinking about "ones that are even less fortunate, the ones who lost their lives. It's just terrible. And why? What do people get out of this? It's just crazy."
Contact Jeff Gammage
at 610-313-8205, firstname.lastname@example.org, or
on Twitter @JeffGammage.