Mom Thinks Blue Mark On Daughter’s Knee Is Bug Bite, Doctor Says It’s From A Black Widow

Kristine Donovan, like any perceptive mom, noticed a small, bluish-purple bruise on the back of her 5-year-old daughter Kailyn's knee. Kristine assumed it was a regular bug bite. Little did she know it was something much more dangerous.

When Kristine discovered the bruise-like bite, she figured it had occurred in the family's backyard.

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"She never felt it bite her,” Kristine said to CBS Boston. “It could have been in her jeans, in the location where it bit her. We just don’t know.”

The parents hesitantly let her go to school the next day.

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But when Kristine received a call that Kailyn had a fever, Mom and Dad didn't hesitate.

They quickly took the little girl to her pediatrician. The doctor took one look at the bite and said she needed to go to the hospital immediately.

Within a day or two, the bite had gotten worse, turning black.

Infectious disease specialists at UMass Memorial Hospital confirmed the unexpected: The bite had been caused by a black widow spider.

Black widow venom kills the flesh around the bite, which was why Kailyn's had turned black.

Thankfully, the little girl received treatment and the bite is healing, though she is walking with a limp.