The death of a five-month-old boy in his bouncer was part of a systemic failure of social services at Surrey County Council, a safeguarding review has concluded.
It found there were missed opportunities to help the family of a 'loved and happy' child.
Baby Acer, who was born during a COVID lockdown, died from 'sudden unexpected death in infancy' in 2021.
The review said there could have been a pre-birth risk assessment and an 'unwise' decision was made to close the case in March 2020.
The council said changes would be made and lessons learned.
Lead reviewer Moira Murray said: 'That Acer was a loved and happy child was evident from the way mother and father spoke about him and from the many photographs on display.'
But her report said Acer was a twin baby born prematurely during lockdown and not able to receive the same monitoring.
It said Acer returned to a cramped, overcrowded home where both parents smoked.
The mother took prescribed medication and co-slept with her babies, and because the father had been arrested, she had to care alone for five children.
Recommendations for Surrey Safeguarding Children Partnership included more support for practitioners tackling unsafe sleeping arrangements.
Surrey County Councillor Sinead Mooney, cabinet member for children and families, said steps had been taken to improve practices.
She added: 'The report also recognises the significant impact the outbreak of the COVID-19 pandemic had on this case.'
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