The gemarra in Kiddushin 17b says that a non Jew inherits his father. My question is according to the Achronim1 who say the concept of "rov" doesn't apply to non Jews, how can a non Jew know who their father is to inherit them? The gemarra in Chullin 11b says a Jew can only know who their father is based on a rov, which according to these opinions, non Jews can't use.
A potentially related question is how is a non Jew proven to have transgressed arayos relations that have to do with the father (such as the one's father's wife); maybe he's not his father. Unless the amount of evidence needed to be liable for arayos is less than for a Jew, as they don't have the idea of והצילו העדה2 (which makes it beis din's obligation to avoid the death penalty if at all possible).
1 Rav Shlomo Landau, the son of the Nodeh BeYehudah (בשו"ת נובי"ת (אהע"ז סימן מ"ב, Chasam Sofer (יו"ד סימן י"ט), Pri Megadim (מש"ז סימן ס"ב סק"א) and ובפתיחה להל' תערובת (פ"א חקירה ג'). Two students of the Chasam Sofer also assume this: Machane Chaim (ח"ב יו"ד סימן ו') and Maharam Shik (או"ח סימן קמ"א). Rav Asher Weiss however holds rov does apply to non Jews, and uses this gemarra as a proof. However the Machane Chaim loc. cit. says רוב בעילות אחר הבעל doesn't apply to non Jews. That point seems to be a subjective disagreement.
2The Machane Chaim loc. cit. talks about this.