A larger choice of medical marijuana strains, or varieties of cannabis, is especially important to Hyman, who has been working for a decade to help his daughter, Rebecca, who has a severe genetic disorder that gives her seizures. Now 13, his daughter is a Florida medical marijuana patient. Hyman said his family still hasn’t found the best marijuana strains for Rebecca, though marijuana helps shorten the length of her seizures from as much as five hours to 20 minutes.