Why babies get sick so often, and quadraphonic record players

Everyone remembers record players, in fact they are making a massive comeback. But what about quadrophonic record players? This week on Lost in Science Stu takes a trip back in time to explain the science behind what used to be cutting edge technology, how does it work, and why it never took off.Also on the show Chris investigates the science to tackle a question on the mind of many young parents; why do babies and children get sick so often and why is it that adults, with their mature immune system, catch these sicknesses as well.