A surrogate mother.
A person who carries luggage for someone else is often called a porter, from the Latin/Frendh/Italian words meaning "to carry".
An armourbearer is a person who carries armour for another person.
When a person feels what another person feels by touching them it is called Extra Sensory Perception (ESP) or someone that is very astute of human nature and then it is called intuition.
Someone who is apprenticed is a person who works for another person so that they can learn a trade.
Such a person can be called a gold digger.
An organism that carries a disease-causing microorganism from one host to another is called a vector. An example of a vector is a deer tick carrying Lyme disease.
A bag-carrier is a person who carries another person's bags.
Hod carrier
Caddy.
Magistrate
a caddie
Posture.