"We have to be the guinea pigs." Sophie's Story (Cannabis for Kids, Part 2)

Tracy and Josh Ryan's daughter, Sophie, was a typical eight-month-old girl until the day her eye began twitching. An MRI showed that she had an optic pathway glioma brain tumor. Given how young she was, the only option was to begin chemotherapy, though the Ryans were told that the tumor would probably shrink only slightly. Convinced that the chemotherapy wasn't doing enough, they began to research other options.

Click here to read more on what scientists are discovering about marijuana online in National Geographic magazine

Some parents are turning to cannabidiol (CBD) oil, a cannabis extract with little or none of the psychoactive compound THC, to treat their children who have cancer and epilepsy. The oil is currently legal in more than a dozen U.S. states, but the supply is limited. The science also lags the law—dosing standards haven't been set, and the effects of long-term use are unclear. Many doctors believe that more research is needed. In "Cannabis for Kids" a few parents share their experiences navigating the uncertainties of medical marijuana in America as they try to help their children.