An infamous fraudster from Hampstead Garden Suburb who stole £20million from friends 25 years ago has now admitted stealing £2m from his in-laws.

Robert Miller stole £2m from his wife’s family’s pension trust after his elderly and sick father-in-law, Mark Spivack, made him the agent to the trust.

He had previously been jailed for six years for stealing £20m while director of Dunsdale Securities, having eventually handed himself in after going on the run.

After the Dunsdale scandal in the 1990s, Mr Spivack and his wife supported Miller, helping him buy his home in Eastholm, Hampstead Garden Suburb, paying for his children’s school and university fees and loaning him money for failed business ventures.

Mr Spivack, who died in 2012, set up a fund with his wife to support his family after his death. It was previously worth over £6m.

In 2008 Miller helped manage the trust as Mr Spivack, who was becoming increasingly unwell, deemed him “proved trustworthy”.

Miller, known by the family as Robbie, even read the eulogy at his father-in-law’s funeral, before beginning his scheme to trick his widow out of huge sums of money.

A civil claim by the trustees was heard at the Royal Courts of Justice on Monday.

In her statement, Mrs Spivack said: “I was at my most vulnerable, having been married to Mark for more than 50 years, and relied entirely upon Robbie and placed a great degree of trust in him.”

She went on to describe how Miller persuaded her to sign away cheques to businesses that did not exist and, once he began to get nervous about being caught, pressured the elderly widow into signing disclaimers saying she was to blame for any mistakes made in the business.

She added: “I was very reliant on Robbie to assist me in the relation to the fund, because I was still mourning the loss of Mark.”

Dena Loftus, Mr and Mrs Spivack’s daughter, revealed that Miller and wife Naomi lived a “flamboyant and ostentatious” lifestyle, despite having no obvious source of income other than £20,000 per year for running the trust.

Ms Loftus suggested the carefully-saved pension fund was spent on Caribbean holidays, cleaners, dog walkers, designer clothes and daily beauty treatments.

She and her mother both said Mrs Miller launched a series of verbal attacks on Mrs Spivack after discovering she had sought the financial advice of someone other than Miller. Ms Loftus described these as “dawn raids” during which she would “come to my mother’s home shouting and screaming loudly and continuing to berate her for going to an independent professional”.

This “threatening and aggressive” treatment left Mrs Spivack “shocked and scared” of her own daughter.

A source close to the family described Miller as “the lowest of the low”.

They said: “This is even more sickening than last time because he is doing it to people who cared for him. His mother-in-law has had to deal with this while she is a grieving widow. It is disgusting, what he has done.”

The family friend added: “Mark was not a lavish spender.

“He was a hardworking man and he set up the fund to create security for his family. He made his money in his furniture business and set up the pension fund to keep it safe.”

Miller has admitted liability in the case and has been ordered to pay the amount in full within two weeks. He has said that his wife, who was named as a second defendant, knew nothing about the scam.