This article discusses the concepts of happiness, emotional well-being and mental health in the light of recent work on children's spirituality, to argue that such a consideration can help to avoid simplistic and individualistic views of each. Distinguishing between happiness as short-term gratification and as longer-term flourishing, the latter is presented as involving the search for meaning. Critiques of programmes designed to develop emotional well-being are discussed. The reasons for patterns of emotional response are explored, including models of attachment and prior and present experience. The importance of adults being emotionally attuned to children to help build up the attributes associated with good mental health is emphasised. For happiness and emotional well-being to be explicit ends in themselves, they would tend to promote introspection and a sense of vulnerability. They should be seen as by-products of children flourishing as a result of sensitive relationships and the types of activities through which children's resilience and sense of agency are reinforced.