The 11-year-old son of the woman charged with blackmailing a mother and daughter, who were found dying in a hotel, is to give evidence against her.

Jack Cotton is set to take the stand against Linsey Cotton at Paisley Sheriff Court later this year.

Ms Cotton, 32, denies trying to extort thousands of pounds from former Liberal Democrat council candidate Margaret and her daughter Nicola McDonough in 2013.

They were discovered severely injured at the Premier Inn in Greenock, Inverclyde, more than two years ago. They died later in hospital.

Jack, a primary school pupil and his sister, Lauren, 15, are give evidence from behind a screen during Ms Cotton's trial.

Ms Cotton is alleged to have said the McDonoughs would be imprisoned for 20 years, and that Nicola, 23, would be attacked in jail unless they gave her £5,500.

Fiscal depute Fraser Gibson told a pre-trial hearing: "There are vulnerable witness applications in relation to the accused's two children - Lauren Cotton and Jack Cotton."

He told Paisley sheriff, James Spy, that special measures were to be put in place for 11-year-old Jack's evidence, which will see him testifying from behind a screen so he does not see his mother.

After hearing that Ms Cotton required further mental health assessments, the trial was adjourned until October.

The time the Crown have to prosecute Ms Cotton, of Addiewell, East Lothian, was also extended until October 30, 2015, at midnight.

Court papers claim Ms Cotton, 32, made the threats towards Margaret and her children Nicola, Kevin, 35, and Michael McDonough, 34, between May 1 and 16, 2013.

Nine days after the first threat, Mrs McDonough, a social worker with Renfrewshire Council, was injured in the hotel and died in hospital. Her daughter died three days after the incident.

Ms Cotton allegedly told them they would be jailed because they had breached a "confidentiality clause" in relation to medical treatment for a Stephanie Wilson or Johnstone.

Prosecutors allege thatWilson is a fictitious person, made up by Ms Cotton when she created a fake online dating profile.

She denies repeatedly contacting former RAF man Michael McDonough using the profile, talking to him and his family while pretending to be Wilson

She also denies pretending to him and his family that Mr McDonough was in a relationship with the fictitious woman and pretending to them that she was various people that knew Ms Wilson she is said to have made up.

She has also pleaded not guilty to repeatedly pretending that Ms Wilson had been seriously injured, had a number of medical conditions, was seriously ill and was receiving treatment.

She allegedly told the McDonoughs that Wilson needed resources and money to make sure she received the care and support she - and her relatives - required.

The indictment against Ms Cotton also alleges that she said "a confidentiality clause" was in force which restricted the release of information about Ms Wilson and that it may be easier for Mr McDonough to see her if he were to get engaged to her.

Ms Cotton also denies introducing herself to Michael McDonough and the rest of his family as one of Wilson's friends.

The Crown claim she took £6,685 in cash and items, including mobile phones, jewellery, household goods, appliances, services and an engagement ring from the family and at RAF Lossiemouth.

She denies the charges, and also attempting to defeat the ends of justice and a further pre-trial hearing has been set for September.