LAST year, my 9-year-old son Leopold and I were preparing for a mother-son ski trip to Keystone, Colorado. I introduced a new rule: we would say yes to everything. Leopold is a picky eater, surviving mainly on chicken nuggets and yoghurt. He often hesitates to try new things. He says it’s because he has phobias, like heights, spiders, and the dark, but I think he just has normal childhood jitters.