Reports of child neglect in the UK have soared by more than 60% in the last five years, a children's charity has warned.
The NSPCC said it dealt with nearly 19,500 calls and emails from concerned adults in 2016/17 - the highest number of child neglect reports it has handled in a year.
Some 87% of reports were serious enough to be referred to social services or the police, including some cases involving children under five, it added.
The NSPCC said a growing number of people were contacting its helpline about parents struggling with alcohol and drugs who were regularly leaving children unsupervised so they could go drinking.
But the charity warned the full scale of the problem could be "much greater" and urged the Government to commission a national study to measure the extent of child neglect and abuse in the UK.
NSPCC chief executive Peter Wanless said: "Neglect can have severe and long-lasting consequences for children, and can also be an indicator of other forms of abuse. This is why it is so important for anyone suspecting a child of being neglected to contact the NSPCC Helpline, so we can alert the authorities to quickly step in and help those in need.
"At the same time, it is vital we understand the true nature and scale of child neglect in the UK so we can collectively tackle the fundamental causes. Therefore, a Government-commissioned, nationwide prevalence study on child abuse and neglect needs to be conducted, and sooner rather than later."
According to the NSPCC, child neglect was mentioned in more than a quarter of calls to its helpline last year.
The charity received 19,448 reports of child neglect in 2016/17, compared with 12,110 in 2011/12 - a 61% increase.
Kate Mulley, director of policy and campaigns at Action for Children, said: "These worrying figures add to the growing evidence that we are failing our most vulnerable children.
"The Government simply cannot continue asking local authorities to provide children's services with one hand tied behind their back. Savings targets have left them with little option but to close family support services that are proven to spot and address the signs of neglect before it's too late.
"We urgently have to re-invest in community-based family support services to prevent this crisis spiralling."