|Hair color||Auburn (s1-s15), Orange (s16-present)|
|Residence||Crosswire Estate, Elwood City|
|Family||Ed Crosswire (husband),|
|Book debut||Arthur Goes to Camp|
|Cartoon debut||"Arthur Goes to Camp"|
|Voiced by||Jennifer Seguin|
Millicent is a monkey who is depicted with a pale complexion, short auburn hair, a green headband, a pink shirt with a row of three buttons and a fish symbol, turquoise shoes, and a yellow wristwatch.
Her original design was seen in a Crosswire family portrait inside of a tent at camp on a page in Arthur Goes to Camp, first published in 1982. In her original design, she had short brown curly hair at the top of her head, brown monkey fur, and was wearing a gray blouse and a necklace. She was absent for over 10 years and was brought back in the cartoon in Season 1, and completely redesigned.
She loves shopping, but in the episode "Lights, Camera, Opera!," she says that she likes opera even more.