Magdalena Zalinska, 44, was being sued in the High Court by the brother of Danny Truell over claims she obtained the money by “undue influence” before he died of a neurological condition in 2019.
The divorced mother-of-two was at the centre of a legal fight with the family of millionaire former banker Mr Truell.
The lawsuit saw Ms Zalinska, who was left a large chunk of Mr Truell’s £18million estate, accused of being a prostitute.
Edi Truell, 61, claims Ms Zalinska was his brother’s paid carer from 2012 and did not live with him.
Magdalena Zalinska was left more than £1million in the former Goldman Sachs banker’s will, in which he described her as his “partner and dependent”.
However, Ms Zalinaka’s body was discovered by police on Saturday who broke down her door in Clapham, south London, after neighbours raised the alarm, reported the Daily Mail.
The death is not being treated as suspicious.