A 26-year-old Wisconsin woman died of sepsis just days after feeling sick with the flu. 

Katie McQuestion, who just got married in September, was the "picture of health," her mother told ABC News

McQuestion began to feel ill on a shopping trip with her mother on Dec. 29 and went home sick from work the next day. Then, on New Year's Eve, she called her mother and told her she felt sicker than she'd ever felt before.

She went to the emergency room where the doctors said she had a high heart rate, low blood pressure and a low temperature. Her mother said McQuestion was given anti-nausea medication and something to help her sleep. 

Twelve hours later, the doctor called McQuestion's parents to warn them that she had made a quick turn for the worst, reported ABC News.

"They told us sepsis had set in, and it was too late," her mother told ABC News. "By that time, all her organs had begun to fail. There was nothing they could do." 

McQuestion also suffered a heart attack. 

"To go from not feeling good to dying is just -- there's no words," her mother told ABC News. "It just breaks my heart. She was such a great kid." 

Sepsis, an illness in which the body has a severe response to bacteria or other germs, sometimes occurs after the flu - usually when a patient has underlying conditions such as asthma or lung disease. Sepsis can also occur if the flu turns to pneumonia, which is bacterial. 

McQuestion had her flu shot this year, but the Centers for Disease Control and Prevention announced that it's not a good match for the mutated version of the virus making its rounds this year. 

As McQuestion's family members mourn their daughter they say they hope her story will help prevent other deaths from flu-related sepsis.