Mandy Moore, also known as Homeless Person That May or May Not Be Mandy Moore is a famous singer and actress, who guest appeared in " Snowflake Day: A Very Special Holiday Special".
When Joan of Arc failed to recognize the magic of "Snowflake Day", she walked out into the alley (she was in a mall) to let off steam. Suddenly, the lid opened, and Mandy appeared. Joan ranted to her about how the holiday was just meant to promote the Greeting Card Industry, (whom tried to shoot at her from a roof). Mandy said that the kids were lucky to be getting their spices from the main holiday mascot, Snowflake Jake and that she had to eat the salt off the road after the ice froze it over. She then proceeded to ask for fifty cents, to which Joan called her greedy, and walked off to sabotage Cleopatra's Snowflake Day party. She returned seconds later to ask her if she was Mandy Moore, to which she denied, telling her that the mic she was wearing didn't even work. When Joan persisted, she said that you'd be surprised by how many "ab machines" you'd find in dumpsters, and that she had a trainer.
She appears later again spying on Joan at her house, while Joan continued to plot against the holiday. They later met in an alley. This time, she insisted on showing Joan the spirit of the holiday. While they began to walk to their destination, Joan again asked her if she was Mandy Moore, which only angered Mandy, and prompted her to scream at Joan. Near the end of the episode, they arrived at Joan's old house, which was now populated my homeless people. They were all having fun, even though they had nothing. Joan realized now that the spirit of the holiday was, and they headed back to Joan's home.
While everyone's stories were coming to a satisfied conclusion, cannons could be heard outside. This was what was presumed to be Snowflake Jake, and Mandy led everyone to the home's basement. Joan realized that Mandy had disappeared once everyone was in the closet, and assumed she was an angel. As it turns out, Mandy was still upstairs. She and her homeless accomplices carried the home's belongings into a van and drove off.