Every mother secretly wants to know if her son has a large cock. A big cock should
mean more sex for him, which should equate to grandchildren carrying on the bloodline.
This concern for insuring the survival of extended generations is a biological function
in most women. Once a mother knows her son is hung like a horse, how can she not
want to fuck him herself while fantasizing of having his baby. If the opportunity
should present itself where she feels safe that no one will ever find out, she will
usually risk having sex with her son just to feel his cum splashing against her cervix.