All Creatures Great and Small will return with a fresh season on Channel 5 shortly and meanwhile, the broadcaster has been showing some of the previous episodes.

The heartwarming family drama charts the lives of siblings Tristan (portrayed by Callum Woodhouse) and Siegfried Farnon (Samuel West), alongside James Herriot (Nicholas Ralph) as they rescue animals at Skeldale House veterinary surgery.

The programme draws from the novels by Alf Wight, the actual veterinarian, with Tristan and Siegfried inspired by the genuine Brian and Donald Sinclair.

Whilst the show is recognised and cherished for brightening viewers' days, some of the actual individuals have endured devastating experiences.

Brian Sinclair was born in 1915 and his father James, a leather producer, died when Brian was merely two years old.

Brian had a seldom-discussed elder sister, Elsa Vaughan, who wed at St Robert's Catholic Church in Harrogate and it was Brian who escorted her down the aisle.

Elsa married Cyril Russell in 1934, meaning Brian would have been approximately 19 years old then.

Little more is documented about Brian and Donald's sister, and she receives no mention in the Channel 5 version of Wight's novels.

In the programme, Tristan and Siegfried share a turbulent relationship which accurately portrays the connection between the younger and elder veterinary siblings.

History Extra noted: "The real brothers shared a complex relationship, with Donald often exasperated by his younger brother's laid-back approach to life.

"Brian took a decade to complete his course at the Royal Veterinary College in Edinburgh, and at Donald's expense."

During his youth, Brian had contemplated pursuing dentistry, but developed a passion for veterinary medicine after helping his cousin, who was a local vet.

He was employed by his brother whilst studying and following his graduation, he came back to his brother's practice at 23 Kirkgate in Thirsk, Yorkshire.

All Creatures Great and Small airs on Channel 5