The Only Way Is Essex sisters Sam and Billie Faiers wrote to a judge on Friday to try to save their stepfather from prison.
But their plea did not stop an Old Bailey judge jailing David Chatwood for the equivalent of four years.
He pleaded guilty to conspiracy to steal £1 million-worth of gold and silver bullion from a lorry in Belgium in October last year.
Sam and Billie Faiers arrive at The Old Bailey
Judge Richard Hone said he had read a letter from Chatwood, 58, and "also a letter from his daughters who find him helpful in their shops".
But this would not alter his sentence because Chatwood was a principal organiser of the theft.
The boutique-owning television sisters, along with Sam's boyfriend Joey Essex, waved from the public gallery with their mother Sue Wells as Chatwood was led away.
Judge Hone said that with time served since pleading guilty in April, Chatwood would serve two years and nine months.
He had been recalled to prison because he was on licence from a 2001 sentence of 12 years for drugs and firearms offences.
Jason Bartfeld, for Chatwood, said: "Unique to Mr Chatwood's case is the media profile of his daughters. who are sitting in court.
"That, to Mr Chatwood, brings an additional sense of shame at the adverse publicity they have had to suffer, and will no doubt suffer, as a result of his actions."
The sisters, who live with their parents in Sawyers Grove, Brentwood, Essex, left court posing for photographers but refusing to comment.
The court was packed with family and friends of five other defendants involved in the plot.
Judge Hone said it was a "well organised and sophisticated" conspiracy involving the use of lorry driver Brian Mulcahay as the inside man.
The British lorry was travelling through Belgium en route from Switzerland to Birmingham.
Many of the defendants were "professional and expert criminals" who had pleaded guilty to conspiracy to steal, with the exception of John Corley, who was found guilty.
Mulcahay, 46, of Grosvenor Road, Westcliff-on-Sea, was jailed for three years and six months.
Stanley Rose, 75, of Iver, Pilgrims Hatch, Brentwood, was jailed for four years.
David Gale, 55, of Hansells Mead, Harlow, and Gary Cummings, 51, of Anne Way, Ilford, all Essex, were each jailed for three years.
John Corley, 53, of Tankerton Road, Whitstable, Kent, was given six years.
A seventh man, Matthew Middleton, 42, of Crows Road, Epping, Essex, also pleaded guilty and will be sentenced at a later date.
The Faiers sisters had been due to give evidence at Corley's trial but were not called.
The court was told Mulcahay was discovered by police locked in his vehicle in Belgium on 4 October after ringing his employers to say he had been robbed.
Chatwood was seen to contact some of the other accused conspirators four days later at a Harvester restaurant in Dartford, Kent.
Nine days after the robbery, most of the bullion was discovered in an apartment and a hotel room in Antwerp which had been rented by Rose.
The robbers were captured within days and had been unaware that they had been watched by police as they hatched their plot.
Gale's girlfriend Sheron Mancini, 53, was cleared in September of trying to smuggle two small gold bars in her bra.