A MOTHER who involved her son and daughter in a murder plot has been jailed for life.

Sharon Hollinsworth bludgeoned her partner Andrew Oates, 44, to death with at least 20 blows from a hammer at the home they shared in Peterhead, Aberdeenshire.

However, at the High Court in Edinburgh defence lawyers exposed Mr Oates as a drunken, bad-tempered bully who dabbled in the occult and conspiracy theories and was obsessed with extreme violence.

After police found Mr Oates's body trussed up in a tarpaulin ready for burial in the garden, they also discovered the family had exchanged texts about weapons and trawled the internet for tips on the use of sleep-inducing drugs and how to make a killing look like self-defence.

Sharon Hollinsworth, 44, who admitted murder, conspiracy to murder and attempting to defeat the ends of justice, was told she must serve at least 11 in prison before she can apply for parole.

Christopher Hollinsworth, who admitted conspiracy to murder his father, was jailed for four years and two months.

Natalie Hollinsworth, his half- sister, 22, who admitted conspiracy to murder and attempting to defeat the ends of justice, was jailed for a total of five years.

Last night Mr Oates's family said they would never come to terms with losing him.

The family also gave their support to a set of proposals made by Peter Morris, whose sister Claire was murdered by psychopath Malcolm Webster in Aberdeenshire in 1994.

The proposed system would mean families whose relatives have been murdered would not have to live in the same street as those accused or convicted in relation to the crime.

Judge Lord Doherty told Sharon Hollinsworth he accepted Mr Oates was "a difficult man to live with".

He added: "I accept he was a controlling personality and you suffered abuse from him during your relationship."

But the judge told all three accused this could not justify or excuse what they did.

In a statement, the victim's family said later: "We would like to redress the picture that has been painted of Andrew. He was kind and generous man, much loved and is missed by his mum, dad, brothers and sisters.

"His family wish him to be remembered as the beautiful person that he was. His death was unwarranted and totally unnecessary and he will never be able to defend himself against some of the accusations that have been made about him."

The three had been accused of murdering Mr Oates in Peterhead, on Friday, October 22, 2010.

A trial was halted when not-guilty pleas to murder from Christopher and Natalie were accepted.

Advocate depute Kath Harper, prosecuting, told how the three accused went to Grampian Police headquarters in Aberdeen early on the Sunday morning. Fomer part-time firefighter Sharon Hollinsworth said she had killed her partner, claiming she had hit him with the hammer after he attacked Christopher.

Ms Harper said police seized mobile telephones and a laptop that revealed the build-up to the murder.

Christopher had a text message from his mother on his mobile phone asking for a heavier hammer.

Experts also found evidence Natalie had been searching for information about the effects of hammer blows to the head and the law on self-defence.

Sharon Hollinsworth was found to have been searching websites for information on the so-called "date-rape drug" rohypnol.

She also texted her daughter: "It's a place we were dragged 2" and "all I want 2 do is protect u both". She added: "I hate him wi a passion n want him gone sooner rather than l8r".