Mary Beth (voiced by Christina Applegate) is a museum tour guide who narrates the life story of Manolo's adventure and journey to a group of young kids who visited the museum. Mary Beth is the Human counterpart of La Muerte, who works at Fantasyland National History Museum and was Princess Cindy's number one babysitter.
Ever since Mary was 18 years old, She really loves babysitting babies until she works at the National History Museum. Mary took a day off from the museum and babysits Cindy while Casey Jr. and Tillie were away. Once arrived at the castle, Mary loves playing with Cindy by tickling her, blowing raspberry at her belly and building a tower with blocks. But, Mary accidentally knocks the tower down and Cindy began to cry when she comforts her. When feeding time, Mary feeds Cindy with the blueberry yogurt. Mary gives Cindy a bath with bubbles, She hugs and kissed Mary's cheek. When Cindy began to feel sleepy, Mary rocked her to sleep while using the music box. After Mary puts Cindy into her crib, She give her a kiss. Then, C.J. and Tillie came back and they were very impressed with Mary doing very great job babysitting Cindy. Mary was happy to be babysit Cindy.
Mary Beth wears a blue jacket over a white dress, a white bandanna on her neck, and black high heels. She has long orange hair, blue eyes, red lipstick, and wears small blue hat on the side of her head.
Mary Beth is a very kind lady and can be somewhat playful as she led The Detention Kids into the secret room. While babysitting Cindy, she was very kind and playful to her.
- The Real Mary Beth is from Fantasyland.
- Mary Beth, La Muerte's Human counterpart, made her debut in Fantasyland Rescue.
- Mary Beth will first meet Princess Yuna, Lightning McQueen, Mater, Dusty Crophopper, Dipper and Mabel Pines in Fantasyland Rescue.
- Mary Beth first met Prince Edmond in ????.
- Mary Beth will be Princess Cindy's best babysitter ever in The Daughter of C.J. and Tillie.