Granting Immunity

S16 E19: Pornographic photos from 15 year-old Savannah Biel's (guest star Hayden Tweedie) house party quickly circulate around her Tribeca high school and go viral. Barba's (Raúl Esparza) efforts to arrest the student responsible for posting the images is stalled when several suspects fall victim to a fast-moving measles outbreak. When Benson's (Mariska Hargitay) foster son also catches the illness, she investigates a group of mothers who may have falsified their children's medical records. Meanwhile, Amaro (Danny Pino) receives some distressing news about his son.