A woman who used a cushion and scarf to strangle and smother her seven-year-old son on the day of a custody hearing has been jailed for at least 18 years.
Lesley Speed, 44, was found with cuts to her neck after killing Archie Spriggs during a bitter custody battle.
The boy died at his home in Rushbury, near Church Stretton, Shropshire, on 21 September.
The judge accepted Speed, who was convicted of murder, had a “chronic” mental illness.
Archie’s father, Matthew Spriggs, claimed the authorities dismissed his concerns about his son’s safety and missed opportunities to prevent his death.
The trial at Birmingham Crown Court had heard Speed was in dispute with her ex-partner, and was “stressing out” about the custody hearing.
Jurors were told how Speed was found with cuts to her neck and wrists in a bathroom, having killed Archie in his bedroom.
The judge accepted she had tried to take her own life after the murder, having left a “chilling” note for Mr Spriggs.
Speed denied murder and claimed she had found her son hanging from his scarf in his bedroom.
Her partner Darren Jones, who discovered Archie on his bunk and his girlfriend lying wounded in the bathroom, said Speed had told him she smothered her child.
The judge, Mr Justice Nicol, acknowledged Speed suffered from “longstanding and chronic” mental health problems but told her: “You may have believed that it would be harmful for him to live with his father… but, even if your belief on that score was genuine, it cannot begin to excuse your action.”
He said Archie was “a playful and bubbly child” and his teachers described him as “chatty and popular, kind and caring”.
The judge told Speed: “There can be no greater abuse of trust than to kill a child whom you should be protecting.”
Archie’s father said those tasked with protecting his child favoured his ex-partner because she was a woman.
In a victim impact statement read to the court, he said: “There is something wrong with a system which allows one parent to dismiss legal proceedings without consequence and an even bigger problem when, despite laws on equality, the assumption is that a mother must be ‘good’ and a father ‘bad’.
“I did all I could to protect my son but was denied the support I needed to do so.
“One person committed this heinous act against an innocent little boy but others were also complicit. Archie’s death could have been avoided. He should be with me now.”
Defence counsel Rachel Brand QC submitted Speed had suffered from a depressive illness for several years, which led to “distorted and negative” thinking.