After the tragedy of Jessica and Holly, the editor of CBBC Newsround Online, Tim Levell, looks at how real the risks are for young people.
Should I be worried?
The short answer is 'no'.
The search for Jessica and Holly dominated the news for nearly two weeks. But that shows how rare and unusual a crime like that is.
If children were taken every day, then you wouldn't hear anything about it in the newspapers or on the television.
Although their stories - and those of children like Sarah Payne and Millie Dowler - are very sad, they happen very, very infrequently.
Safer streets
In fact, the latest information suggests that Britain is safer than ever for children.
In the last ten years, the number of children who have been murdered has dropped by a quarter.
It's now fewer than three out of every million.
By comparison, more than two hundred children per million die in road accidents (and even that is lower than it was ten years ago).
It's our fault!
To be honest, part of the problem is all the news around us - newspapers, 24-hour-news, the internet.
It means these cases get reported much more than ever before, and can make us more worried than we should be.
So don't worry! It's helpful to remember a few rules, and you can see those in our Tips for Staying Safe.