A teenage girl who killed her 18 month-old niece ‘to get the evil out of her’ was locked up indefinitely in a mental hospital today.

Julia Nguyen, 19, of Hornsey Road, Holloway, smothered Mya Nguyen while babysitting at her brother’s home on August 17 last year.

When the parents returned to the house in Vale Terrace, Harringay, she refused to hand over the lifeless child, the Old Bailey heard.

Nguyen also told them that Mya was evil and “she had been getting the evil out of her.”

She later told police: “It is in the hands of God now. I removed the spirit. I’m the only one who can undo what I did to Mya.”

Paramedics restarted Mya’s heart but she died three days later.

Nguyen was charged with murder but pleaded guilty to manslaughter on the grounds of diminished responsibility after being diagnosed with schizo-affective disorder.

Prosecutor Brian Altman QC said her family said had noticed a change in the teenager when she returned to the family home after living with friends.

He said: “Her mother heard her listening to religious music. She would dance and then laugh like the devil and make references to witchcraft.”

Judge Richard Hone QC ordered her to be detained indefinitely under the Mental Health Act.

He said: “The death of Mya is a family tragedy and one in which you deeply share. You exhibited florid symptoms of schizo-affective disorder at the time.

“However there is no sign of any assault or any restraint.”

The judge said he was also influenced by a statement from Mya’s parents Jimmy and Annie that described Nguyen as “a vulnerable young woman who is clearly troubled.” They added: “Julia will live with the guilt for the rest of her life and incarcerating her serves no meaningful purpose.”