Natalie suffers from a blood-bourne curse known as endokataric parapoena, or Shafiq's Syndrome. It's not well-understood by healers, but it's thought in some circles that abstaining from using magic may ease symptoms. Originally studied by pureblood French witch Amandine Shafiq in the early twentieth century, its known symptoms are:

• Chronic widespread pain.
  
• Episodes of intense and painful hallucinations.
  
• Episodes of fatigue and weakness.
  
• Hypersensitivity of all five senses.
  
• Stunted magical development.

Her hallucinatory episodes are rare, occurring once every six months or so, but are completely debilitating. In addition to her hallucinatory episodes, Natalie also suffers from episodes of sensory overload, which are more frequent. Her daily medications are mostly focused on pain management, suppressing her hyperactive senses, and getting her sensory overload under control. There's not much to be done for her hallucinatory episodes since they're so poorly understood.

Natalie probably inherited this condition from the Prince side of the family, as it tends to surface most frequently in children whose families are stringently pureblooded. Ironically, the Princes-at-Large consider her poor health and lacking magical abilities to be a consequence of her mother's blood impurity.