You can expect to see all the major royals attend Princess Eugenie's October 12 wedding to Jack Brooksbank, but don't forget about the Ferguson side of the family. The bride has three aunts and an uncle through her mother Sarah, Duchess of York, alone.

Princess Diana's sister Lady Jane Fellowes notably gave a reading at Prince Harry's ceremony this spring, so keep your eyes peeled for the other "Fergies" likely in attendance — two of them have already served in a royal wedding party.

Sarah Ferguson famously married her ex-husband Prince Andrew in 1986 at Westminster Abbey. But before she became the Duchess of York, Fergie was the daughter of Major Ronald Ferguson and his first wife Susan (née Wright). The couple met at a debutante dance in 1955. Their first daughter, Jane, arrived two years later before Sarah in 1959.

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A picture taken from the Ferguson family album shows Sarah Ferguson, the Duchess of York (right) with her sister Jane at their family home Dummer Down House.

After his army career, Major Ferguson worked as polo manager to Prince Charles, a post he held for three decades, according to the Telegraph. He divorced his first wife in 1974, when Susan married polo player Héctor Barrantes and moved away to Argentina.

The two sisters stayed with their father on their 876-acre family farm in Hampshire for most of their childhood. In 1976, Major Ferguson married Susan Deptford (now Lady Swinburn) and had three more children, Sarah and Jane's half-siblings. Susan Barrantes passed away in a car accident in 1998 and Ronald died not long after in 2003 of a heart attack.

The rest of the Ferguson clan will still likely show up at Windsor Castle next month to see their niece get married. Here's who's who:

Jane Ferguson

Ronald and Susan welcomed their first child on August 26, 1957. Jane is two years older than Sarah, which is the same age difference as Beatrice and Eugenie.

"Oh my God, we got into so much trouble!" Jane remembered in an 2002 essay for the The Times. "Once, we were in Mum's room and Sarah got hold of Mum's pearl necklace. Then she got a pair of scissors and cut in between each pearl, so the necklace fell apart. She was the naughty one and I was the goody-two-shoes. I must have told her off hundreds of times."

At 15 years-old, Jane met her future husband, Alex Makim, who was working on her father's farm as a stablehand. The couple married four years later when she was 19 and moved to the Makim family's 9,000-acre ranch in Australia, People reported.

The couple had two children together — Seamus and Ayesha — but eventually split in 1988. Jane later remarried Rainer Luedecke in 1994 and had her youngest daughter, Heidi, two years later.

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Jane Ferguson and Rainer Luedecke pose at the Cypress Lake Resort in Australia on March 1, 1997.

Jane later revealed that she suffered many miscarriages in between those pregnancies, but her sister helped her through those difficult moments. "Each time, I was left asking myself: 'Why me? Why my baby?' But there just aren't any answers," she wrote in The Times. "It's such a lonely world when a doctor can't tell you why these things happen. Throughout this, Sarah has been a pillar for me. Having our own children has brought us closer still. Sarah and I talk to our children a lot more than our parents would have."

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(From left to right) Ayesha Makim, Jane Ferguson, Rainer Luedecke, and Seamus Makim attend a TV launch even in November 2001.

The Duchess of York also spoke of their special bond in a companion essay. "I love Jane with all my heart," Sarah wrote for The Times. "She's the most unspoilt, kindest, most lovely person you could meet. She never takes anything from anybody and she's always making sure her little sister is okay. The sadness is I don't see more of her — it gets very lonely without her."

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The Duchess of York, Princess Beatrice, and Jane Ferguson attend the memorial service for Major Ron Ferguson on March 24, 2003.

According to her LinkedIn, Jane currently works in corporate relations for an Australian university and she's also "an accomplished equestrian and a keen golfer." Her daughter Ayesha, a model, got married herself in 2015.

Andrew Ferguson

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Major Ronald Ferguson reads to his children Andrew and Alice at their home on Dummer Down Farm in Hampshire in 1986.

Fergie's half-brother was born in 1978, two years after their father married Susan Deptford. Along with Prince William, Peter Phillips, and Seamus Luedecke, he served as a page boy in Sarah's wedding to Prince Andrew. Like his two younger sisters, Andrew has since maintained low profile out of the public eye. He's no relation to the American journalist of the same name.

Alice Ferguson

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Alice and Andrew Ferguson both served in the bridal party at Prince Andrew and Sarah Ferguson's wedding on July 23, 1986.

Born in 1980, Alice was also just old enough to participate in her half-sister's royal wedding. A few other notable faces joined her: Laura Fellowes (Princess Diana's niece and Princess Charlotte's godmother) and Zara Phillips were also bridesmaids.

Elizabeth "Eliza" Ferguson

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Eliza (center), her mother Susan (left), and her sister Alice (right) arrive at the funeral of Major Ferguson on March 24, 2003.

Born in 1985, Aunt Elizabeth is only three years older than her niece Princess Beatrice. Beatrice, her mom, and Aunt Jane recently attended Elizabeth Ferguson's wedding to Henry Cobb in Hampshire last year.

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