The great-granddaughter of a Civil War-era storekeeper in Tampa, Fla. is suing the city for a 147-year-old unpaid promissory note. With interest, the note is now worth over $22 million.

The financially-strapped city of Tampa, in need of ammunition during the Civil War, issued the note to Thomas Pugh Kennedy on June 21, 1861, the St. Petersburg Times reported Sunday. Kennedy's great-granddaughter, Joan Kennedy Biddle and her family are suing to collect the payment, plus 8 percent annual interest.

"This thing has been in the family since the date on the note, and it has never been repaid," Biddle, 77, told the Times. "My daddy told me, and I certainly believe him."

Tampa City Attorney David Smith told the Times that he doesn't consider the claim valid.

In legal documents, Biddle's attorney argues that the statute of limitations doesn't apply, for at the time the note was issued, the state had no such statute on such documents.

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