Muhammad Ali remained hospitalized Friday in the Phoenix area, battling respiratory problems serious enough to draw family members to his bedside.
The 74-year-old boxing great's respiratory issues have been complicated by the Parkinson's that he was diagnosed with in the 1980s, two people told The Associated Press a day earlier.
The two spoke separately in describing Ali's condition as being very concerning to family members. They declined to be identified because they were not speaking on behalf of the family.
Several of Ali's daughters reportedly flew to Phoenix late Thursday and early Friday to be with their father.
Laila Ali, herself a former boxing champion, posted a picture Friday afternoon on Facebook of her father holding her daughter when she was an infant.
"I love this photo of my father and my daughter Sydney when she was a baby!" she wrote. "Thanks for all the love and well wishes. I feel your love and appreciate it!!"
A spokesman for the former heavyweight champion said in an email Friday that there was no update on his condition. Spokesman Bob Gunnell said a day earlier that Ali was in fair condition and that a brief hospital stay was expected.
Ali's longtime Parkinson's doctor declined comment when reached by the AP Thursday night.