[general] Theory abt how demigod childrens look like

Why do i feel like demigods look more like there mortal parents than they're godly parents im the book,cause we see hades and hazel and they both look so different from eachother, hazel looks more like her mother and looks little to nothing to hades,not tryna be racist or anything, nico and bianca on the other hand probably look more like they're mother too as said here in the sources i found "whom both of her children resemble, especially her daughter" "She had dark brown hair, dark brown eyes and a smile similar to Bianca's." , my headcannon is that most demigod children resemble the mortal lover of that god like a bittersweet momment that he gods do to they're children to remind them of their past lovers,