No. It takes years after birth to develop, so younger girls do not have any. Also, diseases, such as alopecia, may cause a girl to never develop pubic hair, or to lose it later on in life. (Chemo...
Yes, else they shave , wax or have telogen effluvium
alot of people do yes! :) when u start shaving it will generally grow back dark if it isn't already!
Yes, after puberty all girls will have pubic hair.
Yes. Both men and women are supposed to have pubic hair. It is natural and normal, and nothing to be grossed out by. It is a sign of maturity.