One by one, the brightly coloured helium balloons floated up into the wintry sky. They were released at the weekend outside the house in which six-year-old Arthur Labinjo-Hughes was murdered, as a way of trying to show that he had been loved. Of all the harrowing details to emerge from the trial of his stepmother, Emma Tustin, and his natural father, Thomas Hughes, the one that many parents will have found unbearable was a film of Arthur sobbing, “No one loves me.” He had been brave enough to try to tell grownups he trusted that something was wrong, and yet nobody came to save him. He must have felt, at the end, so abandoned. What makes this awful case so haunting is that it reminds us of what too many other children will have experienced when lockdown sealed them off from the outside world. Arthur’s complex tragedy is not, it should be said, a simple story of cruelty hidden under cover of a pandemic. His social workers didn’t, unlike some, have the door slammed in their faces by abusive parents pretending to be frightened of catching the virus. And Arthur himself wasn’t invisible to people who loved and cared about him, even after his school closed and his relatives were confined to their homes. His grandmother, a retired teacher, raised the alarm in the middle of the first lockdown after Arthur confided in her. His teachers also passed on concerns flagged up by relatives, and Arthur’s uncle also contacted the police. Lockdown itself cannot satisfactorily explain why social workers who actually visited the house in which he was being tormented went away convinced this was a “happy household”; the single biggest question facing Solihull’s social services department now is how it came to be fobbed off so easily. Yet all that said, the England children’s commissioner, Rachel de Souza, is right that this case raises wider questions about what happened to vulnerable children during lockdown – when, she has said, serious safeguarding incidents rose by a nearly third. The national inquiry announced into Arthur’s case must now be fearless in seeking answers. De Souza told the BBC’s Andrew Marr Show that lockdown had been “such a shock to the whole nation that it weakened the system of support”, but that system has been perilously weak for years. Social services were overstretched and underfunded long before the pandemic hit, which brought with it a surge in reports of domestic violence as families were trapped indoors. The reopening of schools and nurseries will have triggered another rush of new referrals as children came back under the watchful eye of professionals. Like the NHS, social services are now running to catch up with a terrifying backlog, but without the same injection of extra cash and public clamour for something to be done. Everyone sympathises with the need for children who missed school during the pandemic to catch up on what they’ve missed academically. But there is no such national outcry over what might be called social recovery, or the urgent need to help children horribly damaged by being trapped at home with abusive or neglectful parents, even though bringing their maths back up to scratch looks positively easy by comparison. There is growing concern too within children’s services over a minority of families who seem to have fallen off the radar during the pandemic and not come back. With health visitors and GPs still conducting appointments over the phone, some babies born during the pandemic may not have been seen face to face by professionals for nearly two years. To recognise this long tail of risk is not to say that lockdowns themselves were a mistake. In the spring of 2020, and again that winter, the virus trapped Britain between a rock and an impossibly hard place, forcing ministers to balance the hundreds of thousands of lives potentially saved by shutting down the country against what everyone feared at the time could be a heavy price paid by women and children at risk of violence in the home. But it is to say that we now have a moral obligation both to protect those children better in future waves of the virus – one reason ministers are now so determined to keep schools and nurseries open, come what may – and to stop them becoming scarred for life by their pandemic experiences. It’s too late, sadly, to save Arthur Labinjo-Hughes. But it’s not too late to invest in services that will help countless other children growing up in less murderous but still miserable circumstances, and we owe it to them to do better. Gaby Hinsliff is a Guardian columnist