The third episode of the series to be Christmas-themed – A baby is having problems controlling the left side of her body, along with multiple miniature seizures before doctors discover the right side of her brain is malformed due to a Cytomegalovirus infection; a PR executive suffers a year-long ailment that turns out to be a cyst caused by Echinococcus granulosus tapeworms infecting her spleen; seizures ruin a schoolteacher's Thanksgiving, and when they worsen around Christmas, doctors discover a pork tapeworm cyst.