Why is the sea salty?How far away is space?Why can''t I tickle myself?Why can''t we live forever?Children ask the most interesting and challenging questions. But how are we supposed to answer them...?At last! Expert answers to those big questions children ask, with help from:Sir David AttenboroughHeston BlumenthalKate HumbleAlain de BottonPhilip PullmanDr Richard DawkinsBear GryllsDame Jacqueline WilsonJarvis CockerDame Kelly HolmesNoam ChomskyJessica EnnisDerren BrownMiranda HartTracey EminHarry HillA C GraylingDr Christian Jessenand many more!