Children are developing permanent problems with their vision because they are not being given eye tests early enough, optometrists have warned.
An Association of Optometrists survey of 1,200 people indicated a quarter of school-age children had not been taken for a sight test by their parents.
While some schools do offer screening, the tests are less comprehensive than those provided by Optometrists free on the NHS.
One in 50 children will develop amblyopia, lazy eye where vision does not develop properly. The NHS recommends that children should be screened for the condition when they turn four because it becomes harder to treat after the age of six.
Treatments include glasses and using an eye patch or eye drops to obscure the vision in the stronger eye to make the weaker one work harder.
Jane’s daughter, Eve, was diagnosed with amblyopia at the age of seven "It made me feel like a terrible parent, really, because you want to do your best by your children and then finding out that there is a problem that could've been sorted earlier, but you weren't aware of it, was really hard to handle."
In contrast, Chloe, five, was diagnosed with amblyopia at the age of three and was young enough to use an eye patch.
"If her eyesight had been left the way it was, then the eye wouldn't have been within the legal driving limits, so it would have restricted her in future life," said Chloe’s mum.
"Catching conditions early can be massively important for a child's development.
"For amblyopia, treating a condition early means that the chances of improving the vision in that eye are a lot better.
"All children under 16 are entitled to an NHS-funded sight test.
"It's really important for us to make parents aware that this is available for them and available for their children to access."