Who is Peter Phillips and Zara Tindall’s Mysterious Half-Sister, Stephanie?
Captain Mark Phillips shares a complex family tree beyond his children with Princess Anne. While Peter Phillips and Zara Tindall are well-known royal grandchildren, they have a half-sister, Stephanie Phillips, born in 1997. Additionally, DNA tests confirmed New Zealand’s Felicity Tonkin as another of Phillips’ daughters.
Who is Stephanie Phillips?
Stephanie Phillips is the daughter of Captain Mark Phillips and American equestrian Sandy Pflueger. The couple married in 1997 and later divorced in 2012.
Born the same year as her parents’ marriage, Stephanie is 20 years younger than her half-brother Peter and 16 years younger than her half-sister Zara.
Like her father, a gold medal-winning Olympian, Stephanie is an accomplished equestrian. She served on the jury for the dressage and eventing competitions at the 2016 Olympics.
How close is the Phillips sibling relationship?
Evidence suggests a close bond between Stephanie and her older royal half-siblings. Stephanie served as a bridesmaid in Peter’s 2008 wedding to Autumn Kelly and Zara’s 2011 wedding to Mike Tindall.

The support was mutual during Stephanie’s 2022 wedding to William Hosier. Peter and Zara attended the event, and their daughters—Savannah, Isla, Mia, and Lena—served as bridesmaids.
Is there another Phillips sibling?
Yes, Felicity Tonkin was born in New Zealand in 1985. A DNA test in the early ’90s reportedly confirmed that Captain Mark Phillips is her father.
While reports indicate Mark paid child support during Tonkin’s youth, the relationship differs from Stephanie’s. Reports state that Tonkin has never met her royal half-siblings.
What happens next for the family?
The family may gather again for Peter’s upcoming wedding to Harriet Sperling on June 6, 2026. Because British tradition typically involves young girls as bridesmaids, Stephanie is unlikely to be in the wedding party.
However, it is widely speculated that the rarely-seen sister may attend the ceremony to support her brother.
Frequently Asked Questions
Who are the children of Captain Mark Phillips?
His children include Peter Phillips and Zara Tindall (with Princess Anne), Stephanie Phillips (with Sandy Pflueger), and Felicity Tonkin.
What is Stephanie Phillips’ professional background?
She is an accomplished equestrian who served on the jury for the 2016 Olympics’s eventing and dressage competition.
Has Felicity Tonkin met Peter and Zara?
No, reports indicate that she has never met her royal half-siblings.
Do you think extended family bonds are stronger when they share a common passion like equestrianism?