A horrified mother has told how her young daughter began clawing at her own skin and cowering from an "evil monster" after she developed a rare disease that attacked her brain. Erin Smolinski, 38, was left terrified after little Grace, aged three, began hallucinating about a sinister figure and panicking about escape. She suffered seizures, lost the ability to walk and her speech deteriorated from whole sentences to uttering single syllables. Grace was rushed to Lurie Children’s Hospital in Chicago, Illinois, USA, where neurologists diagnosed rare autoimmune encephalitis. The life-threatening condition causes the body’s immune system to attack healthy brain cells, which causes the organ to swell.