Sarah, Duchess of York, has shared the story of one of the most heart-breaking tragedies in the history of the royal family in an exclusive interview with HELLO! The Duchess reveals how, in a travesty of justice, the Queen's great-great-great-grandmother Princess Louise – mother to Queen Victoria's husband Prince Albert - was separated from her two young sons, banished to a tiny German hamlet and never allowed to see them again for the rest of her life.
Watch Sarah Ferguson talk to HELLO!
Now, almost two centuries after Louise's death, Sarah has made a TV documentary in Germany, where HELLO! joined her as she retraced Louise's footsteps, scoured historical archives and visited her tomb in a bid to find out the truth.
"She was discarded by her husband – Ernst I, the Duke of Saxe-Coburg-Saalfeld – and sent to St Wendel," Sarah explains. "Whatever she had done to upset Ernst – who it seems was tired and bored of her and wanted to divorce – to have to leave her two boys and never see them again was, for me, beyond words.
MORE: Prince George and Princess Charlotte to have starring roles at wedding?
Sarah has a close relationship with Prince Andrew and their daughters
"I wanted to know what Louise had done so terribly wrong that she should be taken from her children on that dank, rainy 26 August day – Albert's fifth birthday – put in a carriage, discarded and written out of history."
The filming struck a chord with Sarah, whose own mother, Susan Barrantes, left home when Sarah was a young girl.
"I just don't know what it would be like for me to not be with my girls. I really couldn't fathom it," says Sarah, who is mother to Princess Beatrice and Princess Eugenie.
"One of the best things I've done with my life is that my daughters and I are like a tripod. The girls are very supportive of me and I am very supportive of what they do.
READ: Prince William's poignant birthday gift revealed
"The key is to always be there, but never to wrap them in cotton wool. We work in unity and [ex-husband Prince] Andrew and I are focused on being good parents together. We are bigger than friends. We learn from each other, support each other and understand it's about communication, compromise and compassion."
Sarah says she hopes her mission will allow Louise to speak from the grave. "When I stood by her tomb I felt the cold wind and had goosebumps. There was just a peace and calm," she says. "I feel very proud that we are giving Louise her voice and have honoured what an incredible person she must have been."
For the full interview see this week's HELLO! Magazine