Javie, I think it is different for everyone. I have a PWS who tells me that he stutters the WORST with his family! He says he is more fluent with his friends.
I for one hardly stuttered around my family and friends, but I stuttered everywhere else. In fact, my family had a hard time believing that I stuttered unil they would see me with other people or would hear me stuttering on the phone.
I would say that I stuttered most at work and to authority figures, now I love being able to speak at work and answer the phones!