Frederica (Fred for short) is a princess doll. She loves birthdays and pretend that every day is her birthday. Fred is a high spirited girl with lots of ideas for adventure. She is a nice doll overall. Fred is caring and generous.
Fred has purple skin and orange yarn for hair. She has a green and polka-dotted dress. Her tights are white with orange stripes. Frederica's crown is gold in the first stanza if the theme song and in Knights of the Snack Table she was dressed as a damsel in distress with a green crown and a green dress.
Fred appears in every episode of Blue's Room.