Jill Riches, who has a card shop at Leigh-on-Sea, near Southend, discovered the letter which was written in 1912 in the shop window the other day and is baffled about how it got there.
"It was bizarre. It came out of nowhere. It was literally folded up in the shop window. It is to 'Cousin Daisy,' which is my great aunt Daisy Peel, from a cousin Edith. Cousin Edith had written the letter from Hawthorn House in Welshampton," she said.
Miss Riches, who is her family's archivist, says that previously she had no knowledge of there being any Shropshire relatives and is now hoping that anybody in the county who can add information will get in touch.
She can be contacted at email@example.com by email.
She says her great aunt's maiden name was Cookson and she lived at Crawshawbooth, near Burnley.
Jill, who has had her shop for about 10 years, does not rule out a supernatural explanation for the appearance of the letter.
"It is so weird. The shop used to be a school many years ago and I have been told by a local historian that there is still a presence there of the old schoolmaster," she added.
"And apparently my great-grandmother, the mother of Daisy, was a well known local psychic. She was Mary Ann Cookson, nee Townsend."
Written from "Hawthorn House, Welshampton, near Ellesmere," the letter is dated December 9, 1912, and reads: "Dear Cousin Daisy, I received the skirt and thanks so much, it suits very well. We are all very pleased with it, be sure and thank Auntie. What do you think of the new baby? I never was so surprised in my life as I was over that.
"Well, dear Daisy, we shall soon have Xmas here, so I am sending you a prayer book if you will please accept it, also the half crown for the skirt. I was so pleased to have a letter from you, hoping to hear from you again soon; love to Uncle, Auntie & Cousins and yourself, hoping all are well, I remain, Your loving cousin, Edith."