In the hand-written note, Charlotte pointed out that, "All the girls did was sit at home, go to the beach, and shop, and they had no jobs but the boys went on adventures, worked, saved people, and had jobs."
The boys even got to swim with sharks, Charlotte wrote.
Charlotte ended her letter with a simple request, "I want you to make more Lego girl people and let them go on adventures and have fun. OK!??"
Representatives at Lego did not respond to ABC News' requests for a comment.