Piper Lowery had a fever that soared to 105 degrees.
It hurt for her to walk, and she was breathing heavily, her mother said. She was also bleeding from her nose and vomiting blood.
On Jan. 16, just four days after she got sick, Piper collapsed in the parking lot of a children's hospital in Tacoma, Wash. By then, the H1N1 flu had already attacked her kidneys.
Piper died shortly before 12:30 p.m. that day. She was 12 years old.
Her mother, Pegy Lowery, is now urging other parents to get flu shots for their children.
Lowery's own daughter was afraid of needles, often bawling when they touched her skin; so she never pushed Piper to get a flu shot, she said. And Lowery, of Port Orchard, Wash., said she always thought they were optional, not a necessity.
That view has since changed.
"I don't want it to happen to somebody else," Lowery told The Washington Post. "I don't want them to lose their child. It's pretty devastating. There's nothing like it."
To get her message across, Lowery is knitting infant hats as part of a Fight the Flu Foundation campaign.
The goal is to crochet 100,000 hats this year, with 2,000 to be donated to a hospital in each of the 50 states, according to the foundation. Each shipment will be packed with educational materials and a story from a mother who lost her child.
So far, Lowery has made more than 700 hats.
Her goal is to encourage parents to have their infants vaccinated at six months.
The number of deaths associated with seasonal influenza varies from year to year. The Centers for Disease Control and Prevention estimates that from the 1976-1977 flu season to the 2006-2007 season, death totals have ranged from 3,000 in one season to as high as 49,000.
It's difficult to calculate an annual estimate, because flu seasons are unpredictable and often fluctuate in length and severity, according to the CDC.
While most people recover from the flu in several days, some develop a wide range of complications, including sinus and ear infections, inflammation of the heart or organ failure, according to the CDC. Young children, pregnant women, adults ages 65 and older, and people with chronic medical conditions such as asthma and diabetes are more likely to experience complications.
An average of 20,000 children younger than 5 are hospitalized because of flu-related complications, according to the CDC.
Since 2004, the number of flu-related child deaths among children reported every flu season has ranged from 37 to 171, according to the CDC. As of Sept. 15, 85 children from 33 states, the District of Columbia and Puerto Rico had been killed by the flu during the 2015-2016 season.
The CDC recommends that nearly everybody who is at least six months old be vaccinated. Exceptions include people with life-threatening allergies to the vaccine. For this flu season, the CDC recommends the flu shot and the recombinant influenza vaccine. Recommendations for influenza vaccination also are available.
In recent years, the CDC has been faced with a growing anti-vaccine movement, the rise of which has alarmed public-health experts. Jack Wolfson, a physician who became a de facto spokesman for anti-vaxxers, told The Post's Terence McCoy last year that "people need to learn the facts" about vaccines and the chemicals in them.
Lowery said her decision to not get a flu shot for her daughter was driven not by resistance to the idea of vaccines, but by not knowing their importance.
She said she did everything she could to help her daughter after she got sick, and Piper was taken to the hospital several times. And, Lowery said, she doesn't really know whether a flu shot would have kept her daughter from dying.
"It may have made a difference; it may not have made a difference," she said.
Lowery said she doesn't want to blame anybody for her daughter's death, saying she would rather focus on the positive impact of Piper's death. Other parents have told her that they got their children vaccinated because of what happened to her daughter, Lowery said.
"Believe me, I would take her back within a second," she said. "But there's been a lot of good that's come out of this that's helped other people. She's impacted so many lives, I cannot tell you. I can't go back and rewrite history."
Piper was buried about a week after she died.
According to Piper's obituary, Lowery got pregnant with her after trying unsuccessfully for 10 years to have a child - and after one last attempt at in vitro fertilization.
Piper's brother, Noah, was born 2 1/2 years later.
"Piper loved to sew with her Mama, she loved dolls and creating mini doll food," her obituary states. "She loved crafting, making tiny things with her beautiful long fingers. She enjoyed life to the fullest riding dirt bike, climbing trees, swimming, jumping on the trampoline."
Now, Lowery's Facebook page is filled with memories of her daughter - pictures, plus messages about how much she misses Piper.
She also regularly posts messages about flu vaccination.
"Believe me nothing is worse (than losing) your children," she wrote last week. "For the rest of my life I will fight for this cause!!!!"
Kristine Guerra is a general assignment reporter for The Washington Post.
(c) 2016, The Washington Post · Kristine Guerra