The partner and the brother of a banker are locked in a High Court battle, with the man describing the woman as a "call girl" who conned the late businessman out of £4million from his £18m fortune.
Danny Truell made his fortune with Goldman Sachs, before becoming the UK's best-paid charity boss, earning £3million a year as chairman of the Wellcome Trust.
In later life, he was diagnosed with motor neurone disease and multiple sclerosis.