Received this response from Hasbro tonight. Here's the original email trail:
Dear Jennifer,
We
wanted to get back to you since our email did not fully answer your
daughter’s questions. We love to hear from all of our consumers,
especially children, so we hope this response will help clear up any
questions.
Dear R____,
We
agree that girls are equally as important as boys and want both boys
and girls to have fun playing our games. When you play the Guess Who?
game, you have the same chance of winning the game whether you picked a
card with boy or a card with a girl.
We
love your suggestion of adding more female characters to the game and
we are certainly considering it for the future. In the meantime, you
will be pleased to know that we have additional character sheets that we
can send out to you in the post if you ask your mum to send us your
postal address. Alternatively, you can visit http://www.hasbro.com/games/ discover/guesswho/Guess-Who- Characters-en_GB.cfm to download and print additional character sheets so you can have lots of different fun people`s faces to choose from. You will be happy to know that our downloadable sports character sheet includes an equal number of boys and girls.
We hope your mum does not throw out your Guess Who game!
Please let us know if we can be of any further assistance.
Kind Regards,
Hasbro Consumer Affairs
Hasbro UK Ltd


