Rare is the modern parent who hasn't complained that their child is "addicted" to screens. For most of us it's a throwaway comment stemming from irritation with a teenager's incessant messaging, or a toddler having an "iPaddy" when the tablet has been taken away. But evidence is mounting that children's acute dependence on gadgets could become as damaging to their physical and mental health as recognised addictions to drink or drugs.
Earlier this week, a British Heart Foundation study warned that just one in 10 toddlers in the "iPad generation" is active enough to be healthy. So many frazzled parents use screens as a "dummy" to pacify their children that most two-year-olds don't even manage one hour a day of activity.
There's no need to spell out the damage this will do to future generations' wellbeing.
So how do you keep your child's tech usage at a healthy level, whatever their age - and how do you know if you've already got a screen addict on your hands?
To start with toddlers, any parent knows how much easier it can be to hand them a gadget when you need to keep them occupied. There's no point demonising screen time altogether - it has its place, even for this age group, and there are developmental benefits - but too much can certainly make little Jack a dull boy. Marooned on the sofa, he won't be getting the physical activity he needs, or the inter-personal interaction that small children learn from. Not to mention free, uncluttered thinking space to daydream, use his imagination or observe little wonders such as raindrops racing down a window.
Catherine Steiner-Adair, research associate at Harvard Medical School and author of The Big Disconnect: Protecting Childhood and Family Relationships in the Digital Age, says the key is not to turn to tech as the default distraction: "Children learn from play, especially preschoolers and primary-aged children. Be sure yours spend more time playing and learning from hands-on engagement in the real world than they do on screens."
Even as they get older, it's wise to delay buying them their own gadgets; an eight-year-old might want the latest iPad or smartphone, but they certainly don't need it. Sticking with shared family tech makes it easier to take it away - and to monitor what children are doing online.
Crucial, too, is setting a decent example. Given how many of us are glued to our gadgets - jumping to grab our phones every time a message bleeps, or checking the football scores under the table during Sunday lunch - it's unsurprising that our children soon learn to do the same. And when they do, it's going to be pretty difficult to stop them without your own behaviour undermining your efforts.
With that in mind, Steiner-Adair warns that parents should worry if screen dependence starts to override previous pleasures. So when that sports-mad son no longer wants to kick a ball, or the once-sociable teen now only interacts online, a tech addition could be taking hold.
According to clinical psychologist and psychotherapist Dr Jay Watts, the key characteristic of a true addiction is "when someone has a persistent, compulsive habit of doing something," adding that "addictions on-screen aren't that different from those off-screen, in nature".
Putting that into a screen-time context, if your son or daughter no longer seems to be able to control when they get online or cope when they can't - displaying hallmark withdrawal symptoms such as anxiety, temper tantrums and denial - this should be a red flag.
Additionally, Steiner-Adair suggests looking for less obvious behaviour changes that are being triggered by the urge to power up. "If a child is lying about computer use, sneaking it in, avoiding school or other social activities, is more tired, irritable and withdrawn than normal, and becomes defensive about their use and unable to cut back, there's cause for concern."
Screen usage may be the inter-generational struggle of our times, believes Dr Watts, but she cautions against panic. "If you're educating your kids about sensible usage, in most cases there won't be a serious issue. And there is some research showing that various video games can really aid concentration and brain agility."
For parents grappling with more moderate Minecraft or iMessaging enthusiasts, then, simply encouraging - or enforcing - sensible screen usage should nip any potential addiction in the bud. Your armoury here includes setting family-wide rules - perhaps no gadgets during dinner (parents too), or when you have visitors over, and certainly not for an hour or so before bedtime, as screen glare disturbs sleep.
For better or worse, tech is a significant part of our lives now - our children's being no exception. Our job, as parents, is to ensure it doesn't take over and become life itself.