During a tele-town hall meeting with Florida voters Sunday, Santorum said his family experienced a "very difficult 36 hours" after 3-year-old Isabella was hospitalized, ABC News reported.
His daughter, nicknamed Bella, suffers from Trisomy 18, a rare and serious genetic disorder that is fatal for about 90 percent of children before or during birth. The condition is caused by the presence of all or part of an extra 18th chromosome.
"She's had a miraculous turnaround," the former U.S. senator from Pennsylvania said on the call with Florida voters. "We have a long way to go but she turned the corner and we are very, very grateful."
Santorum said he was at his home in Virginia during the weekend to attend two fundraisers and get his tax files from a home computer but spent most of Friday night with his daughter. By Saturday she needed to be hospitalized.
He did the two tele-town halls from his daughter's hospital room, one with Florida voters and the other with Minnesota voters, ABC News reported.
Santorum thanked callers for their prayers and said his daughter was "alert" and "smiling through her mask."
The Santorum campaign canceled a Monday appearance at an Orthodox synagogue in Boca Raton, Fla., but the candidate was expected to attend events in Missouri and Minnesota.
Missouri and Minnesota vote Feb. 7, but delegates will not be counted in Missouri until their caucus March 17. Unlike Florida, Missouri and Minnesota proportionally distribute their delegates.