Advice to get shy/quiet child to stick up for herself

[username10382]

DD (6years old) is fairly quiet and can be shy in school. She does have friends however some of these friends can be quite bossy and occasionally quite mean to her. She came home upset last week and it took me all evening for her to admit what had happened.
I am a quiet person and I know what it's like to be constantly made to feel like it's a character flaw. So I don't want to try and change her, however, I do want her to be able to somehow stick up for herself/speak up when needed. Anyone any advise/tips/words of wisdom?

[AtlasPine]

Poor little girl - school can be so hard sometimes.

Giving her actual phrases to practice in a role playing situation can help. Will she tell you exactly what the situations are typically?