The fiance of best-selling children's author Helen Bailey faces life behind bars after a jury today found him guilty of murdering her to get his hands on her £3.5m fortune.

Ian Stewart, 56, suffocated the wealthy widow - who owned a holiday home in Broadstairs - after secretly plying her with a sleeping drug and then callously dumped her body in a cesspit.

Her remains were found three months after Stewart - who met Ms Bailey on an online group for widows and widowers - had reported her missing from their £1.5m home in Royston, Herts.

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A court heard how Stewart had tried to hide his crime by telling detectives Ms Bailey had gone to Broadstairs for space and time but later claimed two men called Nick and Joe kidnapped her.

But a jury of seven men and five women took around five-and-a-half hours to find "devious killer" Stewart guilty of the "cynically executed murder that had money as its driving motive".

Judge Andrew Bright QC delayed sentencing until tomorrow.

Stewart, dressed in a light blue striped shirt, blue jeans and a black belt made no reaction as the verdicts were read to him in front of a packed public gallery which included one of his own sons.

VIDEO: Ian Stewart guilty of Helen Bailey murder

When he was asked to sit down, Stewart shook his head after hearing the verdicts but kept a straight face and remained silent throughout.

The jury unanimously found Stewart guilty of murder, one count of fraud, preventing lawful burial, and three counts of perverting the course of justice following a six-week trial.

Helen's brother John Bailey, who gave evidence against Stewart in the trial, was also present to hear the guilty verdicts.

He watched Stewart as the verdicts were read out, but remained silent after the Judge warned the public gallery before the jury entered that he didn't want to hear outcries.

Following the verdict, Helen's brother John released a statement on behalf on the family - which said there will be no celebration.

It said: "When Helen's body was discovered last July, some three months after she had gone missing, we said we knew Helen would wish, like us, for justice to be done.

"We wish to thank the Police and Crown Prosecution Service for their unswerving professionalism and support, and to those individuals who gave up their time to be members of the jury or to give evidence in court, as now the perpetrator of this crime has been brought to book.

"We also wish to thank the many individuals for their support, some of whom have been grieving for their own personal loss - as their acts of kindness have been invaluable to us.

"Our thoughts are very much with Ian's family.

"Despite this victory for justice there can be no celebration. Our families have been devastated and nothing can ever bring Helen back to us, or truly right this wrong.

"A long shadow of loss has been cast over the lives of so many who will always remember Helen with enduring love and affection.

"At her memorial service, we asked attendees to write down what Helen's life had inspired them towards.

"From over 160 affirmative responses, one person wrote: 'To help people when they needed a friend'.

"With these words in mind, we now embark on rebuilding our lives and we respectfully request that we be allowed to do so in peace. Thank you."

St Albans Crown court was told Stewart fabricated a story that Ms Bailey had left a note saying she needed time and space and was heading to their holiday cottage in Broadstairs.

"Our families have been devastated and nothing can ever bring Helen back to us, or truly right this wrong" - Helen's brother, John

But after being arrested, computer software engineer Stewart hatched a plan that two mystery men called Nick and Joe kidnapped Ms Bailey and blackmailed him for £500,000.

The court heard the men were business associates of Ms Bailey's late husband John Sinfield, and kept Stewart at their mercy and swore him to secrecy.

But the prosecution said Stewart used two old friends, Joe Cippullo and Nick Cooke, as inspiration to create an image of the 'kidnappers' who were shown to the jury.

It was heard Stewart killed Ms Bailey to be in line to gain two homes, enough cash to ensure a "very comfortable" lifestyle, pension and life insurance payments from his fiancee.

The court heard on the day Ms Bailey was killed on April 11 last year, she had been using her iPad to search for venues for their wedding which was planned for September.

Her body was dragged to the garage and dumped in the cess pit along with her beloved dog Boris, a dog's toy, a couple of bin bags and a pillow slip which the court heard could have been used to smother Ms Bailey.

On the same day Stewart was seen at Royston Recycling Centre disposing of a large white item, believed to be a duvet which he used to drag her body to the pit.

He revisited the tip days later to ensure the duvet was gone, and reported Ms Bailey missing at 3.37pm on Friday April 15 last year.

Stewart also used his own computer to change a standing order from Ms Bailey's bank account to the couple's joint account from £600 to £4,000.

He then acted out a "complicated charade" that Ms Bailey had left a note saying she needed time and space and was heading to their holiday cottage in Broadstairs.

The father-of-two sent numerous text messages to her phone "leaving a trail" which prosecutor Stuart Trimmer QC said would "give the impression of somebody whose lover had just disappeared".

Mr Trimmer said Stewart "might have got away with it" if he hadn't taken Ms Bailey's phone to Broadstairs days after she was reported missing.

Her mobile phone connected to the router at the cottage, after Stewart told police Ms Bailey had disappeared and she had taken her phone with her.

Ms Bailey's mobile phone has never been found.

Stewart admitted continuously lying to Ms Bailey's family and police as they carried out a 'futile' missing person investigation after he fabricated a cover story she had ran away.

In the months before she died she had been searching online for things such as "falling asleep in the afternoon" and "can't stop falling asleep".

Analysis of Ms Bailey's hair revealed she had been administered sleeping drug Zopiclone from as early as February 2016.

Consultant forensic pathologist Nat Cary told the court Ms Bailey could have been killed in a sleeper-hold but the formal cause of death was undetermined.

Her body was found with no broken bones or signs of a violent assault in the cesspit she once said in banter was a "good place to hide a body".

At the time of her death, Ms Bailey was said to have had assets worth £3,326,316.

The couple had met on a website which was for people dealing with grief after Stewart's wife Diane died in 2010.

In Ms Helen's book released in 2015, When Bad Things Happen in Good Bikinis, she spoke of the grief of losing her husband John who drowned in front of her while in Barbados.

She also spoke of how she had dramatically once told her husband John she was "going to disappear", vanish and start a new life under a new identity.

It also detailed a relationship with GGHW - Gorgeous Grey Haired Widower- who was Stewart, and also dedicated the book to him.

She wrote "Ian Stewart: BB, I love you. You are my happy ending."

Stewart, of Royston, Herts., will be sentenced tomorrow.