If parents spend their lives on their smartphones playing games or using social media they should not be surprised if their children copy them, according to an addiction expert.
Professor Mark Griffiths said worried parents were contacting him every week about the amount of time their children were using social media or playing video games.
Prof Griffiths, himself a father of three, said that threatening his own children with losing screen time was usually enough to get them to do their chores.
"I think I am a socially responsible parent and I get letters and emails every single week from parents saying my daughter is addicted to social media or my son is addicted to Warcraft," he said.
"When I write back I say to them, 'Are you engaged in educational activities? Yes. Are you engaged in physical activities? Yes. Are they doing their chores around the house? Yes. Have they got a big network of friends? Yes'.
"So, I say, 'What's the problem then?'
"The typical reaction is, because it is a waste of time and they should be reading.
"What did I do when I was their age? I watched three or four hours of black and white TV on three channels with my parents.
"I've got three teenagers and none of them watch TV, particularly.
"When I was a kid my punishment was to be sent to my room. My punishment for my kids is, you can now come and sit with us.
"If I want my kids to do anything, screen time is the way.
"If I tell my daughter she will lose two hours screen time unless she does her chores, I don't need to empty the dishwasher.
"Children learn off their parents. I gave up my smartphone a couple of years ago, so my kids know that you can actually live without your phone.
"If you are the kind of parent who is always sat there on social media there should be no surprise if your kids are copying you."
Prof Griffiths, a chartered psychologist and director of the international gaming research unit at Nottingham Trent University, was speaking during an event on addiction at the Cheltenham Science Festival.
He said people can become addicted to gambling, exercise, sex, video gaming and social media.
"It's not the amount of time that you do something, it's the context in the terms of the negative knock-on consequences in your life," he said.
"If we accept that one person is genuinely addicted to slot machines in the same way someone else is addicted to alcohol or drugs then we are saying it is theoretically and practically possible to become addicted to a behaviour.
"If you accept that basic premise, there is no reason someone cannot become addicted to a video game, exercise or sex."
He said that behavioural addictions were all encompassing - and he would find it difficult to play a slot machine and give a lecture - whereas if he were an alcoholic he could work and drink.
Prof Griffiths said tech companies could do more to limit the instant gratification of their products, such as reducing the frequency of notifications and alerts.
"Whether you are a social media operator or a gambling operator, it isn't all about addiction residing in the individual as there are things they do in terms of promoting a product, advertising and the design of the product that will influence whether people become habitual or addicted users," he said.
"I've tried explaining why teenagers become addicted to social media.
"Things like unpredictable rewards, things like every time you hear a beep or fear a vibrate, you immediately attend to your screen. Those things are deliberately designed to distract you from the real world on to your screen.
"The longer you are on the screen the more advertising they can sell. That is using things we have known about for years with gambling and applied to social media.
"The numbers of people genuinely addicted to video games or social media are going to be few and far between.
"There are a lot more who are habitual and we all know people who are constantly looking at their screens."