Prodigy and Havoc begin laying down rhymes together in high school. When their first album flops, they come up with a new sound that's directly influenced by P's sickle cell, and it helps define a generation of hip hop. Plus: Big Twins talks about the sickle cell attack he’ll never forget.     LANGUAGE WARNING: The Realness contains strong language that some listeners may find offensive.  WNYC’s health coverage and The Realness by Only Human is supported in part by the Robert Wood Johnson Foundation, Jane and Gerald Katcher and the Katcher Family Foundation, Science Sandbox, an initiative of the Simons Foundation, and the Alfred P. Sloan Foundation.  Audio of Prodigy on Questlove Supreme is provided by Pandora, which also has a recording of Mobb Deep's classic hit "Shook Ones (Part II)" performed by Nas.