A sadistic dad kept his eleven-year-old step-son shackled in his bed from 8.30pm until 8.30am every day.
He forced him to wear a strait jacket and bondage-style leather helmet - because he was a 'handful'.
The man - who cannot be named in order to protect the child's identity - is a 39-year-old former company director from Yorkshire. He has been jailed for three years. The child's mother - who admitted child cruelty - was locked up for two years.
Doncaster Crown Court in South Yorkshire heard that the boy's mum did nothing to stop her husband's torture of the child. Judge Jacqueline Davies branded the child's treatment 'appalling and grotesque'.
She said: 'It is difficult to understand how you could have done this to any human being.'
The boy is now is foster care.
A neighbour of the family said: 'We'd no idea anything so sick was going on.'
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