The Spiderwick name apparently came from Constance's side of the family, as her niece (more specifically, her brother's daughter) originally was named Spiderwick in surname.
Arthur and Constance bought the Spiderwick Estate on May the 9th, 1905, and moved in shortly thereafter. Arthur was already at this point documenting the Invisible World, and he wrote a note that it hopefully was a lot of Faerie activity in the surrounding woods, which would later show up to be just the case.In 30 years, Arthur continued with his studies. His wife (and the Fey) were getting more and more worried about lifework.
At some point, Arthur and Constance had a little daughter, whom they named Lucinda Spiderwick.
Finally, Arthur was imprisoned by the Elves, when he on September the 6th, 1935, tried to trick the Faeries by giving them the burned remains of an ordinary book, when they had demanded him to destroy the Field Guide.
Constance passed away shortly thereafter, and Lucinda was sent to live with her cousin Melvina's family. When Lucy had grown up to a young woman, she moved back into the Estate. But the Faerie people attacked her numberless times, and finally gave her a possibly lethal curse: they tricked her to eat their food. After that, Lucinda couldn't eat Human food, because the fruit she ate tasted so wonderful that all Human food in comparation was like sawdust and ashes. She could have starved to death, but the Sprites she had played with as a child protected her and gave her food. But one night, Mulgarath and his army of Goblins arrived at the Estate and interrogated Lucinda about the Guide. The Goblins' claws scratched Lucinda, and Mulgarath casted an evil spell which caused her back to get twisted and hunched. Melvina got enough, and Lucinda was sent to Woodhaven Sanitorium for help.After that, Melvina met a man named Grace in surname, which created the Grace family.