In the past she was especially fond of botany and gardening. She lived in the Estate, prior to her death, with Bernard, in an arranged marriage that then sprouted on love. She is said to have earned her fortune by saving the Estate from bankruptcy, during a crisis in sausages of 1892. However, she died before having any descendants to share said fortune with, since Bernard, who was an eccentric painter, one day set fire to a watercolor canvas he was displeased with, setting fire to the entire manor, burning Mimsy alive in her sleep.
In the dining room of the mansion, a portrait of Lady Mimsy can be seen, with a description that reads:
"The haunting portrait of Lady Mimsy Alcorn Shallot was painted on the very afternoon before she perished in her sleep from an unfortunate estate fire. The exact cause of the fire is still a mystery. These days, she's much more transparent. Visit The Von Haunt Estate and your Sims might get a chance to meet her... um... in person?"
Additionally, if the player has a Sim look at said painting, a notification will appear that reads the following:
"Lady Mimsy Alcorn Shallot
Nowadays, Mimsy can be easily found in the Estate lot, wandering around. Her most common actions include treating her garden, walking through the labyrinth and playing the piano next to the wedding arch, in the Estate's garden. She is nicknamed "The Green Lady" or "The Ghost Gardener" by locals. She can also be found at some of Windenburg's bars, if it's Ghost Night.
- She might be inspired by the character Lady of Shalott, from the ballad of the same name, by Alfred, Lord Tennyson, where the protagonist lives on a castle and is not allowed to look over to the city of Cantelot, or else she is cursed. When she does so, she is killed by the cold weather attempting to escape on a boat.
- If she is taken to CAS mode, she will not have a name or surname.
- If she eats an Ambrosia as a mean to get back to life, she'll be a normal Sim again, yet she'll still keep her ghost abilities, like scaring Sims or possessing objects.