The opposition leader of Devon County Council fears vulnerable children could be held in police cells if three children's homes in the county are forced to close.
The County Council instead wants to offer more foster places for children in the future.
Councillor Alan Connet, the leader of the Liberal Democrats is holding a debate this afternoon to try to save one of the homes from closure.
The cost of raising a child to the age of 21 has reached £222,000 as parents pay 58% more than a decade ago, with parents in the South West seeing the biggest hike in costs, according to an annual study. Families here now pay £100,077 more per child than ten years ago.
Education and childcare remain the biggest costs, with 76% of parents reporting that they have been forced to make cuts to meet the financial demands of raising their offspring, the survey for insurer LV found.
The overall figure is more than £4,000 up on last year and £82,000 more than ten years ago, when the first annual Cost of a Child Report was published.
A new child protection centre has opened in Plymouth. The NSPCC will use it to work with abuse victims and target potential offenders in families, where children are considered at risk.