This was exactly the case for Evelyn Frost, who discovered the correct day she should have been celebrating just before she turned 100!
For her entire 99 years on the planet, Evelyn had been celebrating her birthday on 17 April after discovering that she was actually born 16 April.
The mix-up only emerged when she applied for her birth certificate, which she needed to enclose when applying for a 100th birthday telegram from the Queen.
And as the pensioner from Tamworth, Staffordshire, had never had the document before, she was taken aback when it arrived and listed her date of birth as 16 April 1914.
Mrs Frost celebrated her birthday on the correct date for the very first time last week. Her daughter-in-law Fredia was quoted in the Daily Mail saying: "We celebrated on Wednesday for the first time and even Evelyn said it felt a bit weird.
"She is still very surprised and she wants to celebrate her birthday on the 17th as well."
We reckon it's the perfect excuse to have two birthdays!
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