Princess Diana's secret health struggle on her wedding day revealed

The Princess of Wales got married in 1981

When Prince Charles married Princess Diana in 1981 the whole world was watching with amazement, but did you know that the Princess of Wales struggled with a 'cracking headache' all day because of her precious bridal tiara?

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While Princess Diana herself didn't make the omission about her wedding day, her brother Earl Charles Spencer did reveal all in an Entertainment Tonight interview back in 2010. Her troublesome headache, which can be a common issue at a high-pressure event such as a wedding, was believed to be caused by the bride's huge tiara.

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WATCH: See the first moments of Princess Diana as a wife 

Her brother explained: "In the evening we all went to a sort of semi-private party, and she was there, and she seemed incredibly relaxed and happy and I just remember she had a cracking headache too, because she wasn't used to wearing a tiara all morning."

Diana wore her family's tiara instead of one from the Queen

While The Princess of Wales' jaw-dropping wedding dress was her 'something new', impeccably designed by the Emmanuels, her tiara was 'something borrowed' and unconventionally not from the Queen – instead, she wore her own family jewels.

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The family heirloom was the Spencer tiara which was originally created in 1919, and it was a wedding gift to Lady Cynthia Hamilton, Diana’s grandmother, when she married Viscount Althorp.

Her beautiful tiara apparently gave the bride a headache

The beautifully intricate design dazzled as she walked down the aisle, but the weight and structure of it were believed to have caused the tension.

After her tragic death in 1997, the Spencer tiara was returned to her brother Charles and remains within the family collection to date.

Kate Middleton wore a smaller tiara on her wedding day

It is reported that Kate Middleton opted to wear a smaller tiara for her 2011 nuptials to prevent a wedding headache. She sported the Queen Mother's Cartier Halo Tiara, and the glittering headpiece features 739 brilliant-cut diamonds and 149 baguette-cut diamonds. A top tip for brides-to-be considering bridal headwear!

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