When young Bertrand Might was born, his parents at first thought nothing was amiss. But then they began to worry, as his body appeared to be constantly moving, a state they called "jiggly." Then, he seemed to be constantly distressed, and the efforts of his father Matt to calm Bertrand "enraged" him. Matt and his wife Cristina had a series of tests done on Bertrand, which first indicated brain damage. Then that theory was ruled out, and more tests suggested Bertrand had a fatal "error in metabolism". But that hypothesis got nixed too. The whole saga is told by Seth Mnookin in The New Yorker, and you should read it.