"... A legal parent-child relationship entails various rights and obligations including those related to inheritance and support. The court’s ruling is based on the view that the relationship between a father and a child that has been developed over years should not be disestablished only because of the lack of a blood tie. This argument in itself is reasonable. ..."
Read the entire article: http://ajw.asahi.com/article/views/editorial/AJ201407180030