The parents of at least two babies sickened in an infantile botulism outbreak are suing the makers of the ByHeart baby formula at the heart of a nationwide recall.

Stephen and Yurany Dexter, of Flagstaff, Arizona, said their 4-month-old daughter, Rose, had to be flown by air ambulance to a children’s hospital two hours from home and treated for several weeks this summer.

Michael and Hanna Everett, of Richmond, Kentucky, said their daughter, Piper, also 4 months, was rushed to a hospital Nov. 8 with worsening symptoms of the rare and potentially deadly disease.

The lawsuits, filed in federal courts in two states, allege that the ByHeart formula the babies consumed was defective and that the company was negligent in selling it. They seek financial payments for medical bills, emotional distress, and other harm.

Both families said they bought the organic formula to provide what they viewed as a natural, healthier alternative to traditional baby formulas, and they were shocked and angered by the suffering their children endured.

“I wouldn’t guess that a product designed for a helpless, developing human in the United States could cause something this severe,” said Stephen Dexter, 44.

According to federal and state health officials, Rose Dexter and Piper Everett are among at least 15 infants in a dozen states who have been sickened in the outbreak that began in August. No deaths have been reported.

Both received the sole treatment available for botulism in children less than a year old: an IV medication called BabyBIG, made from the blood plasma of people immunized against the neurotoxins that cause the illness.

As investigations into more potential botulism cases continue, ByHeart, the New York-based formula manufacturer, recalled all its products nationwide on Tuesday. California officials reported that at least 84 U.S. babies have been treated for infantile botulism since August.

The lawsuits filed could be the first of many legal actions against ByHeart. Bill Marler, a Seattle food safety lawyer who represents Dexter, noted that “this company potentially faces an existential crisis.”

ByHeart officials did not comment specifically on the new lawsuits but stated they would address legal claims in due course while ensuring families are aware of the recall.

In the case of Rose Dexter, she received ByHeart formula soon after birth when breast milk was insufficient. Her father expressed concern about food ingredients and sought a 'natural option'.

However, Rose struggled with the formula, leading her parents to seek emergency medical care. Similarly, Hanna Everett noted that after using ByHeart to supplement breastfeeding, her daughter Piper became ill, prompting an emergency hospital visit.

Both infants experienced severe symptoms but improved after receiving treatment. As investigations continue, families await the outcome of their lawsuits while focusing on the health of their children.