Tama-chan

Tama-chan is the (approximately 10 year old) next door neighbor of the Bottle Fairies and Sensei-san. She is represented by the colour purple and wears crayons in her hair with a large white ribbon down the back. She is happy to help the Bottle Fairies, who trust her (usually misleading) advice since she seems so self-assured. She occasionally expresses surprise at how childlike the fairies are even though they are supposed to be older than she is. Additionally, she is the mascot of the magazine, Magi-Cu.

(Source: Wikipedia)

As a side note, in episode 12 it is revealed that she is entering second grade, so around 7 would be a more accurate age for her.