Claudia Winkleman's sister Sophie seriously injured in a car crash

Claudia Winkleman's half-sister Sophie has reportedly been seriously injured in a car crash.

Actress Sophie, who is married to Lord Frederick Windsor, the first cousin of the Queen once removed, is said to have been involved in an incident that took place on Saturday evening, whilst driving home from the set of Danny Boyle's new US TV series Trust.

Sophie is Claudia Winkleman's paternal half-sister

According to various papers, the mum-of-two has suffered a broken back and foot as a result of the crash, which occurred when a vehicle swerved to avoid a deer and ended up hitting her chauffeur-driven car.

'It was a terrible shock for the whole family,' a source told MailOnline.

'Freddie's looking after their two girls while Sophie recovers. It will be a long road for her but we're all so thankful she's been told there won't be any long-term problems.

She has made several appearances at official royal events, including Trooping the Colour

Sophie is the paternal half-sister of Strictly Come Dancing host Claudia, and shot to fame in roles across TV and film, including Channel 4 comedy Peep Show, and BBC drama Waking the Dead.

She became a member of the Royal Family when she tied the knot with Frederick at Hampton Court Palace in September 2009. The pair have gone on to welcome two children together, Maud Elizabeth Daphne Marina, born in August 2013, and Isabella Alexandra May, who arrived in January 2016.

Sophie pictured on her wedding day with husband Frederick in 2009

The Daily Mail states that Sophie was initally taken to Addenbrooke's Hospital in Cambridge, along with the drivers of both vehicles, but has since been transferred to London's Chelsea and Westminster Hospital.

No representatives for the star, or members of her family, have yet released a statement about the incident.