Are the children of Adam the descendants of the killer or the victim?

Answer

In the name of Allah, be advised, my son, that one of Adam’s sons, Qabil (Cain), killed his brother Habil (Abel) and fled. There is no authentic chain confirming that Qabil had descendants. After this tragedy, Allah blessed Adam (PBUH) with two other sons, Sheeth (Seth) and Yafith (Japheth), and from them came the children of Adam. Allah knows best.