Why do children and elderly people fall asleep very easily?

Why do children and elderly people fall asleep very easily?

Chris Idzikowski (Director of the Edinburgh Sleep Centre) gives expert video advice on: Why do some people need more sleep than others?; Do children or adults need more sleep?; Do elderly people need more sleep? and more...

If somebody can't control their wakefulness because they're falling asleep and they just can't manage it, it implies that there's a sleep disorder going on. Now with youngsters and children it could just be the fact that they need a bit more sleep. They haven't got enough during the night. With adults it might be more along the lines of something that's going wrong with their sleep and that needs to be investigated.