My own experience of being a working mother of three has seen me change careers and reduce my hours at different points in the lives of my children, with my partner and I relying on a mix of formal settings, such as nurseries, playgroups, and after-school clubs, to informal arrangements with grandparents and friends to help manage the childcare challenge. But, as every parent knows, this carefully constructed house of cards can all too easily come crashing down with something as simple as a missed or late running train - or the dreaded phone call from the school office to collect a sick child.