By Andrew Rafferty, NBC News
SARASOTA, Fla. -- Elizabeth Santorum, the 20-year-old daughter of presidential hopeful Rick Santorum, took to the campaign trail Sunday after the youngest member of their family was rushed to a Philadelphia hospital late Saturday night with pneumonia in both lungs.
The former Pennsylvania senator canceled events throughout Florida to remain with his 3-year-old daughter Bella, who suffers from the genetic disorder Trisomy 18. A statement released Saturday night alerted the public to the emergency, but little information has been available since. One Santorum adviser told NBC News that Bella's condition was improving, but still unstable.
"My dad today is exercising his most important role, which is being a dad," Elizabeth Santorum told a crowd of nearly 250 people gathered in an airplane hanger here.
Speaking briefly to reporters after the event, Elizabeth Santorum would only say her sister "got sick and right now she's in the hospital and we're hoping and praying she will be better soon."
Bella's story has become a staple for Santorum on the campaign trail.
He invokes the story of his daughter, who was not expected to live much longer than birth, in his crusade for life. During the first days of her life, the Santorums celebrated each day by marking her birthday. As her health improved, the celebrations became less frequent, celebrating each week, then each month.
Rick Santorum was taking a rare break from the campaign trail this weekend when Bella fell ill. The candidate held a fundraiser in the Philadelphia-area on Friday and another in Washington, D.C., on Saturday. Preparing his tax returns for public release was another reason he cited for returning home.
But the candidate's absence affected turnout Sunday afternoon. The crowd paled in comparison the more than 3,000 people that Newt Gingrich was able to draw at the same venue last week. Campaign staffers indicated that turnout in this heavily Republican area would be an indicator if Santorum would continue to campaign in the Sunshine State. As of now, he has not committed to being here the night of Tuesday's primary.
Reality TV stars the Duggars will attend the next scheduled Santorum event of the day, and the status of a scheduled event in Boca Raton, Fla., remains unclear. The Duggars family served as surrogates Sunday, with Josh Duggar taking the stage and hitting Mitt Romney, saying the former Massachusetts governor encouraged homosexual lifestyles and made abortions available to women for $50.
"It's been quite a journey, and I think of many nights around our kitchen table talking about starting the journey," Elizabeth Santorum said. "We knew this was not easiest course for our family. We knew there would be hard moments that would test us."
Elizabeth will attend church services Sunday afternoon.