Legal battle over inventor’s multi-million estate

Jack Leonard, a successful engineer who invented a foetal heart monitor, has left behind an estate valued at £5.4 million, sparking a legal dispute between his biological and stepchildren, as reported by The Times.

Leonard, who also ventured into business and helicopter piloting, had children from his first marriage to Audrey Leonard. Later, he married Margaret Leonard and treated her family as his own. At his death in 2019, at age 87, Leonard’s will, written in 2015, divided his wealth equally among both families.

His biological children, Megan, Sara, Jonathan, and Andrew Leonard, are challenging the will in court, arguing that the stepchildren should not inherit. They claim their father lacked the mental capacity to make such a decision in his final years. Sara Leonard, a director in her father’s flying school, emphasised that their contest is based on principle rather than monetary gain.

However, Margaret Leonard’s children – Mark Smith, a 66-year-old business owner, and Elizabeth Leslie, a 57-year-old yoga teacher – along with Melanie Turner’s offspring, argue their inclusion in the will is justified due to their close relationship with Leonard. The court heard of Leonard’s remarkable life, including founding the internationally successful Eurotherm and launching a flying school. Leonard, originally from Manchester, began his illustrious career in Edinburgh, where he invented the heart monitor.

Leonard’s first marriage was in 1958 to Audrey, with whom he had his children. Following Audrey’s death in 1998, Leonard met Margaret through online dating, impressively arriving on their first date in a helicopter. Representing the stepchildren, Thomas Dumont KC argues that Leonard was fully competent when he drafted the 2015 will, which he believes fairly reflects his love for all his family members. The final decision now awaits the judge’s ruling.

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