My younger brother and I share an account and we have filtered chat on right now, but my mom thinks that he is too young to use it and she wants him to use the bubble chat. Is there any way for me to turn on bubble chat for just one character? or will it change it for the whole account? :/
Any settings applied to an account effect the entire account - in your case, this would be the chat setting.
Depending on the age of your sibling & how dedicated to the questing he may actually be, it may work out better to just set him up his own account (attached to your family of accounts). That way, he can have menu only chat & you still retain your open chat.
Just a general note on the chat for all the wizards: ALL chat levels must adhere to the Terms of Use. If you wouldn't say it to your grandmother, please don't say it in game (or even try to!).