When was the last time your children watched a hardcore porn video online? I'm guessing you're all outraged and shouting 'never' but how sure are you about what children are viewing online?

Leaving aside any debate about the rights and wrongs of pornography in society let's be clear about one thing. Children shouldn't be seeing it. But with over four million pornographic websites on the internet, an increasing number of children are learning about sex and personal relationships through the warped lens of adult porn.

On Friday, ChildLine revealed that they have seen a 34% increase in children and young people contacting their counsellors about hardcore adult pornography. ChildLine collects anonymous information on some of the calls. They reveal how boys are increasingly becoming addicted to online porn, while girls are increasingly worried about the consequences. Here are a few examples of things young people said:

'My friend in school has porn on his phone and he showed it to me. Since then I have become addicted to it.'

'My brother puts sex videos on my computer and shows me them. I have asked him to stop but he keeps doing it. My family would be really annoyed if they found out.'

'My friend has upset me. She called me sick because she came round to my house and I showed her some sex videos on the internet. 'I didn't like watching them at first but my dad likes them so I started watching them when he had them on.'

I've spoken to ChildLine counsellors who tell me they are now getting more than 50 calls a month from teenagers who've been upset by seeing hardcore adult pornography. Some said they were worried about becoming addicted to porn. And girls have called the helpline to report that they are being pressured, coerced or even forced into mimicking adult videos by their peers.

Fortunately the government is listening and is currently consulting on whether to strengthen internet safety controls. They particularly want to hear from parents so this is a crucial opportunity to have your say - but you only have two more weeks to air your views. We are calling on the government to introduce an automatic block on online porn to protect children but this is one of three options on the table.

The two alternatives involve combinations of giving parents the option to switch on restrictions to certain content such as pornography, self-harm and social networks. As you can see it's not simple, and we are concerned that the more these decisions are left up to parents the less likely they are to succeed.

Why? Not because we think parents can't make decisions, or that there aren't tech-savvy parents out there. However, parents have said to us many times that they find the current methods too complicated. And there is so much variation in the protection one child would get compared to another we strongly support the first option in favour of a system that automatically blocks all adult content. We believe this supports parents in offering the greatest possible protection for their children.

Putting the onus on adults to have to request their Internet Service Provider to allow them to view pornography online, rather having it freely available to everyone, would go a long way to shield children. No system is ever going to be perfect - and there will always be young people who try to find a way around blocks, out of curiosity for example. So at the end of the day it's also really important that parents talk to their children about the risks they can encounter online.

Parents being frightened or pretending this material doesn't exist is not an acceptable response. We all have a duty to educate ourselves and our children about the world and how to navigate it safely. So, just as we should be talking to our children about road safety or sex and relationships we should also be talking to them about the sexual content they might see online, and why and how they should avoid it. These aren't easy conversations to have but ducking them isn't doing children any favours.

So, after you've read this go and do three things. Check the filters you already have on your PC, and do the same for smartphones, tablets and so on. See if you can get past them. There are lots of tips online. Next, tell the government what you think they should do. And finally, take a deep breath and make time to chat to your children about what they're doing online. Maybe ask for their help, acknowledge they may know more than you, it might be a way to start the conversation.

Then hopefully the next time you open up your web history there won't be any unwelcome surprises there.

Follow Jon Brown on Twitter: www.twitter.com/@jonbrown46