I carried out a quick search but couldn't find anything on this this topic. I wondered if I'm missing something?
Pages 238 and 256 give us the impression that GTS/Charles Casey first travelled back in time to begin his stoking spree by impregnating Hattie. Hattie then gives birth to Esther who gives birth to Irene who gives birth to Rant. All good so far. However, P238 reveals that there was another similar event that took place prior to this chain of events in which 'granny Bel' was attacked at the age of 13 by a person unknown. So the all important question in my mind that I can't figure out is who impregnated 'Granny Bel'?