In a cottage in the New Forest, in the autumn of her life, Esther Rantzen made a decision she would later unmake. She had booked her flight to the Dignitas clinic in Switzerland, packed the paperwork, settled the fee. Then, strangely, she found she was not in enough pain to go through with it. By the time the pain did arrive, months later, her body was too frail for the journey.

It is a detail that says more about courage than any obituary line could: a woman famous for forcing Britain to look at uncomfortable truths spent her last years forcing herself to look at one of the most uncomfortable truths of all. Rantzen, who has died aged 86, built her name across six decades of British broadcasting, beginning as a BBC radio studio manager in 1963 before moving into television research and eventually fronting the consumer series that made her a household face. But it was Childline, the helpline she founded for children suffering abuse, and later the Silver Line, its counterpart for isolated older people, that gave her work its lasting shape. Two organisations, built decades apart, both designed to answer a telephone when nobody else would.

Her family's tribute described "a legacy of compassion and understanding" that would live on through those charities and through everyone who loved her. Prime Minister Andy Burnham credited her with giving "a voice to people who often went unheard," while Kim Leadbeater, the MP behind Britain's assisted dying bill, said Rantzen's defiance had given strength to others facing terminal illness, reassuring them "they were not alone." What lingers, perhaps, is the shape of a life that insisted on speaking plainly about silence itself — the silence of an abused child, of a lonely pensioner, of a dying woman weighing her own final hours. Rantzen spent her career dismantling other people's silences.