Three-year-old Daisy Ramos is a smiling charmer -- blowing kisses, clapping hands, reaching out to a photographer -- but her mother can't help worrying that her daughter might catch a flu virus and develop a life-threatening case of pneumonia.

Daisy's a high-risk patient at the Children's Institute in Squirrel Hill and she'll be at the top of the list for the H1N1 flu vaccine, when it becomes available next month.

Her mom, Olga Sacalxot of Atlanta, Ga., wants to bring Daisy home safe and healthy after her recuperation from the small bowel and liver transplant she had last year at Children's Hospital of Pittsburgh of UPMC.

Daisy's busy right now, getting therapy to help her recover and catch up with the usual toddler skills. Her mom helps her with a feeding program (babies hospitalized with feeding tubes get behind in those skills). She also gets physical therapy (she's not walking), occupational therapy (she's got work to do: it's called play), and speech therapy (Daisy's saying "Mama" and "Bye-bye").

She came to the institute May 19 and has improved her skills, according to her mother, who primarily speaks Spanish.

Ally Kenna, an Echo International translator, helped with the conversation, and said Daisy's mom told of many setbacks her baby has had, sending her back to Children's.

"The love of a mother can push you, and help you do what needs to be done," Ms. Sacalxot said.

Daisy needs to get flu vaccines, Ms. Sacalxot explained, because when she gets a cold, she has trouble breathing and develops pneumonia, which could lead to another month in the hospital.

"Yes. I am worried very much," her mother said. And, because Daisy is learning to feed herself, a hospital stay would mean another setback in that development. She needs nourishment to continue healing from her surgery, her mother added.

Daisy's big sister Ashley, 5, has been staying with their mom at the Ronald McDonald House all summer and plays along with Daisy as she practices scooping oatmeal into a cup.

"She does better with her big sister," Ms. Sacalxot said.

Handwashing at the institute is more important than ever. The young patients are susceptible to infections and the new flu seems to hit them hardest.

It's an invisible enemy. When asked if she feels like she has to guard her child against germs, Ms. Sacalxot said,

"Yes, muchisimo."

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