These ponderings attempt to let themselves be appropriated by the event. (Beiträge zur Philosophie (Vom Ereignis), Martin Heidegger, 1936–38/1989)
https://selectivemutismcenter.org/whatisselectivemutism/
See also
https://www.verywellmind.com/what-is-selective-mutism-3024702
https://www.anxietycanada.com/disorders/selective-mutism/
https://my.clevelandclinic.org/health/diseases/selective-mutism