I also don't believe people generally have children to fulfil a wider societal responsibility. As a parent myself, we had children mostly because we thought it would be nice to have children around. It has been much more than "nice," in a way that I could never really put into words. However, I can honestly say that the maintenance of my own health and wealth into old age has never been remotely a concern; if anything, I spend my time trying to find ways to insulate them from the consequences of an ageing society. I don't see those aspects of parenthood changing.