Princess Diana's Niece Lady Amelia Spencer Is Engaged to Boyfriend of 11 Years

Greg Mallett/ Instagram Greg Mallett and Lady Amelia Spencer

There's another regal wedding on the horizon!

Lady Amelia Spencer, the daughter of Princess Diana's brother Charles Spencer, 9th Earl Spencer is engaged to her boyfriend of 11 years, Greg Mallet. Charles shared the exciting news on his Twitter page along with a photo of the couple kissing — and Amelia showing off her new diamond ring.

"So happy for my daughter, Amelia, engaged to her boyfriend of 11 years, Greg. It’s wonderful to hear them both so excited about their future. Sending them both love, and every good wish for their life together," Charles wrote.

"I love that Greg asked my blessing before proposing," the proud dad added. "Very sweet."

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Both Lady Amelia and Greg also posted swoon-worthy photos on their Instagram pages to announce the news.

Amelia called the day of the proposal — July 22 — the "best day of my life," adding "I can’t wait to spend forever with you @gregmallett I couldn’t love you more."

Greg posted four photos and captioned the post, "I asked the love of my life to spend the rest of her life with me and she said YES. Couldn’t be happier and I love you with all my heart."

Since Lady Amelia's cousins are Prince William and Prince Harry, there's a good chance they will be on the guest list at her wedding. Amelia and her twin sister Lady Eliza and older sister Lady Kitty, attended William's 2011 royal wedding to Kate Middleton.

Dave Thompson/PA WIRE Lady Amelia, Lady Eliza and Lady Kitty at Prince William and Kate Middleton's 2011 wedding

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Just a month after Meghan Markle and Prince Harry said "I do," the couple were all smiles as they attended the wedding of Princess Diana’s niece Celia McCorquodale, the daughter of Diana’s oldest sister Lady Sarah McCorquodale.

Celia completed her bridal look for her June 2018 nuptials to George Woodhouse with the Spencer Tiara, the same stunning headpiece worn by Diana at her royal wedding to Prince Charles in 1981 — and there's a chance Lady Amelia will choose the same headpiece for her big day.

BAV/Geoff Robinson; Graham Harrison/REX/Shutterstock Celia McCorquodale; Princess Diana

BAV/Geoff Robinson Prince Harry and Meghan Markle at Celia McCorquodale's wedding

Prince William and Prince Harry are still close to their late mother's family. Last summer, Diana's sisters Lady Sarah and Lady Jane appeared in the family portrait from Archie's private christening.

Charles Spencer and Princess Diana

Diana was tight-knit with her younger brother Charles, 9th Earl Spencer. He's also spoken out about losing his sister — most famously giving a powerful eulogy at her funeral at Westminster Abbey, making him Diana’s best-remembered sibling.