It has been said (‘Teenagers: A Natural History’: David Bainbridge, 2010) that teenage years are to develop the brain and as such they are the greatest achievement of evolution – the point where all that is special about our species comes into play. For parents of teenagers, it’s our job to look after them while they are incubating their extraordinary craniums. “Adolescence is the reason we live so long, long, long,” says Bainbridge. “Human longevity has evolved because we need to bring up our intensely supported, slowly developing offspring.” And that’s of course intensely important, being a parent at this stage is a constant negotiation between keeping them safe and…