Four in five grandparents believe that young people are under more pressure than previous generations, polling suggests, amid mounting concern about a crisis in mental health.
Experts said children growing up in the shadow of Covid were facing “agonising” waits for help, as they struggled to adjust to life after lockdown.
It follows warnings that some mental health conditions among children have doubled.
Official figures show more than one million referrals of children for specialist mental health help were made last year, with cases rising by one quarter overall since 2019.
The polling by mental health charity Mind involved 2000 grandparents and 2000 parents of children and young people below the age of 25.
In total, four in five grandparents think young people face more pressure now than in their day, while almost two in three think young people are lonelier.
Not seeing friends key factor in mental health
More than half of parents polled thought their children’s mental health had worsened since the pandemic. Of those, three quarters said the inability to see their friends had been a key factor, with almost as many blaming disruption to schools.
Half said lack of access to extra-curricular activities during repeated lockdowns had worsened their children’s mental health, while four in ten said extra time on social media had fuelled their problems.
The charity urged the Government to fund a network of drop-in centres, saying lack of action to tackle a growing crisis “risks failing a whole generation”.
They said the hubs would allow children aged 11 to 25 to seek help early, and without a referral, when they first start to experience mental health problems, with no need for an appointment.
One in three grandparents said that mental health is their biggest concern for grandchildren. Just one in five think the Government is doing enough, with almost as many saying their own mental health or wellbeing had worsened because of their concerns.
Latest figures show one in six children had a probable mental health problem last year - up from one in nine before the pandemic.
Paul Farmer, the chief executive at Mind said too many young people were facing “agonising” waits for mental health help, while their needs were increasing rapidly.
He said: “Mental health is one of the primary concerns of parents and grandparents with only one in five grandparents believing the UK Government is doing enough to support young people’s mental health. Over four in five of all parents are worried about the long-term impact of the pandemic on their children.
“These shocking statistics highlight the crisis parents and grandparents are experiencing first hand when it comes to the mental health of their own children and grandchildren.
“Young people were among the hardest hit by the pandemic because of lockdowns and school closures.
“These latest figures also reveal that parents, who saw first-hand the devastating impact the pandemic had on their children, felt that their child’s mental health was impacted because they couldn’t see their friends or participate in extracurricular activities.”
The polling of parents found nine in 10 wanted young people to get early access to early support when they start experiencing problems with their mental health and wellbeing.
Half were worried that their child’s mental health is now worse than before the pandemic, with just 15 per cent saying the Government was doing enough to support young people’s mental health.
Nine in ten wanted to see the creation of a nationwide network of hubs should be set up, with most saying the Government should fund them.
Government risks 'failing a whole generation'
Mr Farmer said: “The scale of unmet need for relevant and appropriate mental health support for young people is huge and growing. By not acting now the UK government risks failing a whole generation.”
A Department for Health and Social Care spokesman said: “We recognise the pandemic had a significant impact on the mental health of children and young people, and we are taking action to fix this.
“This includes investing £79 million into children’s mental health services last year, enabling around 22,500 more children and young people to access support in their communities, and across schools and colleges.
“We have launched a call for evidence to inform our 10-year mental health plan and we’ve seen the NHS mental health workforce grow by 40 per cent since 2019.”