The teenage daughter of financier Ben Goldsmith has been killed in an accident on the family's Somerset farm.
Iris Goldsmith, 15, died suddenly on Monday afternoon after reportedly becoming trapped when her vehicle, which is said to be similar to a quad bike, overturned.
An air ambulance was sent to the scene near the village of North Brewham after emergency services were called at around 3.15pm.
Police said Iris's death is not being treated as suspicious and officers are carrying out inquiries on behalf of the coroner.
Iris's father is the younger brother of Conservative MP Zac Goldsmith and Jemima Khan, while her mother is Kate Rothschild.
Her parents married in 2003, uniting two of Britain's most wealthy families, but divorced a decade later.
Iris, who attended Wycombe Abbey, an independent girl's boarding school in High Wycombe, Buckinghamshire, died at the start of the school holidays.
The school's headmistress Rhiannon Wilkinson said: "We were all shocked to learn from the family of Iris' tragic death. We extend our deepest sympathies to her parents and family at this sad, sad time.
"Iris was a much valued and loved member of our school community. She was highly regarded in her House and year group. Popular with staff and pupils alike, she was truly thriving in her academic work.
"We are very proud of her and how, in particular, she had blossomed in her GCSE studies this year. Iris was sparky, inquisitive with an effervescent, sunny personality which lit up all around her.
"The whole school community is devastated by such a tragic loss of a happy, well respected, successful young woman. Iris will be hugely missed by all of us at Wycombe Abbey and, in particular, of course, by all her many friends. Iris' family are very much in our thoughts at this very difficult time."
An Avon and Somerset Police spokesman said: "We were called at about 3.15pm on Monday July 8 to a farm in the North Brewham area following the sudden death of a teenage girl.
"The girl's death is not being treated as suspicious and officers are now carrying out inquiries on behalf of the coroner.
"The family ask the media to respect their privacy during this difficult time."
South Western Ambulance Service said: "We were called on Monday at 3.15pm to attend an incident involving a vehicle at an address in North Brewham, Somerset.
"We sent the following resources to attend the incident: an air ambulance crew, a critical care team, a land ambulance crew, and two other paramedic officers."
