Becoming a parent reorganizes the self around another person with a totality that few other life events match — the previous identity does not disappear but is permanently recontextualized, the frame of everything enlarged and complicated. The loss of a child, or the estrangement of one, is an identity wound of corresponding depth: a future self that was being built collapses, and the question of who you are without that particular role cannot be quickly answered. Both the becoming and the losing ask fundamental questions about whether the self can be secured against what happens.
Each step builds on the last.