The Spencer sisters, whose dad is Diana's brother, estate owner and writer Charles Spencer, 51, have been establishing a higher profile recently on social media. The trio includes Lady Kitty, 25, and 23-year-old twins Lady Eliza and Lady Katya Amelia (who's mostly known by her second name). Their younger brother Louis, Viscount Althorp, 21, is a student at Edinburgh University in Scotland.
The young women (who snared the spotlight at cousin Prince William's 2011 wedding to the then-Kate Middleton with their spectacular headwear) and Louis are the children of Charles and his first wife, Victoria Lockwood, the former model who is now a psychologist and addiction counselor in Cape Town, South Africa.
Globe-trotting Kitty, who journeyed to Australia, Italy and the resorts of Ibiza and St. Tropez last year and served as a bridesmaid in South Africa over the New Year, has been linked to Australian weather reporter James Tobin, 35.
Twins Amelia and Eliza attend college in Cape Town, where they were raised following their parents' messy and very public 1997 divorce.
Although Kitty is the oldest, she has gone on the record as saying she believes her younger brother, Louis, should remain as the prime inheritor of the family seat, the magnificent Althorp House. The picture-perfect estate is where Princess Diana is buried where historical writer Charles Spencer mainly lives.
"I'm totally pro-gender equality," Kitty told the December 2015 issue of society glossy magazine Tatler. "But I'm quite happy that that's [going to be] my brother's responsibility. I just think it's the correct way."
And it underlines the continuity of the aristocratic name and family, she believes.
"I like that the house stays within the same family, with the same surname," she said. "I wouldn't want it any other way for the Spencers. And I just know my brother is going to do an impeccable job."
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The four oldest Spencer children also have three half-siblings, including the Hon. Edmund, 12, and Lady Lara, 9, Spencer's children with his second wife, Caroline Freud. (Spencer and Freud divorced in 2007 after six years of marriage.)
Their third half-sibling is 3-year-old Lady Charlotte Diana, the daughter of Spencer and his third wife, Canadian philanthropist Karen Gordon. The toddler not only shares a name with second cousin Princess Charlotte, but was named in honor of her famous aunt who died in a car crash in Paris in 1997.