One of the surviving children of Sarah Barrass and Brandon Machin fears they will also become a murderer “because that’s what mum and Brandon did”.

The two older children – who the incestuous couple plied with prescription drugs in an attempt to kill them before trying to drown one of them in a bath – have been left “emotionally broken”, Sheffield Crown Court heard.

And all four children will be in need of ongoing support, according to a victim impact statement written on their behalf by social workers.

The court heard that the children wanted their parents to go to prison for “300 years”.

Kama Melly QC, prosecuting, told the court: “When (the older two children) were told Sarah and Brandon had pleaded guilty to the murders of their brothers and the attempted murders of them, (one of them) said they were worried they would become a murderer when they were older because that’s what their mum and Brandon did. They said they didn’t want to be like that.”

The court heard that the children did not know that Machin – who is Barrass’s half brother – was their father and had been told their father was dead.

Miss Melly said:  “Both (the older children) are emotionally broken and don’t know why this happened. They repeatedly ask why and how. We don’t have the answers.”

The barrister added: “Both (the older children) keep saying they just want a nice family home.”

She added: “Both say they want their brothers back because it’s too hard without them.”

The court heard that the two youngest children, who are aged under three, never asked for their mother or Machin, even when they are upset.

Miss Melly said the older two were “really struggling knowing they will not see their big brothers again and not seeing their (other siblings) every day.

“They have lost everything.”

She continued: “There’s no doubt that all four children will need ongoing psychological support.

“There’s no way of knowing the long-term effect and impact on their lives at this stage.”

Mr Justice Goss said: “The statement from their social worker on their behalf describes their inevitable confusion, the effect of the loss of their brothers.

“Inevitably they will require a considerable amount of support. The long-term consequences to them and (the younger children) as they grow older cannot be known.”