Grace Harper’s parents would have always described their daughter as a happy, loving young girl.

But, practically overnight, their once happy daughter began having brutal outbursts. These continued for nearly two years, and doctors couldn’t figure out the cause, but it turned out Grace’s behavior was the result of a very rare disease that is caused by strep infections.

The disease is called PANDAS, and its symptoms often lead to the misdiagnosis of mental problems.

PANDAS is short for Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcus. After a child is infected with strep, their body produces antibodies to attack and kill the infection.

If a child is suffering from PANDAS, the antibodies instead attack a part of the brain that controls their behavior.

For so long, doctors didn’t know much about the disease, but now, they are trying to raise more awareness. It’s even become the main topic in a documentary called, “My Child is Not Crazy.”

For Grace’s parents, it took two long years and endless doctors appointments to figure out what was wrong with their daughter, but sadly, her’s isn’t the only case. A 6-year-old girl named Madeline Greenstein also suffered from similar symptoms.

Her mom said she would cry hysterically over nothing and experienced high pitched laughing like something you would hear in a mental institution. Madeline’s symptoms also resulted from PANDAS.

Thankfully, since strep is the cause if this disease, it can be treated with antibiotics. Grace’s parents thought that their daughter’s behavior would set her back in school, but with the right treatment, she is now back to her normal self.