No. But they could do real harm to themselves or others.
5 seconds sound clip from the Step Brothers (2008) movie soundboard.
You can hear this line at 01:06:34 in the Blu-ray version of the movie.
Quote context
[...]
- No. Why would you do such a thing?
- Never, ever wake up a sleepwalker.
- See, that's it. We can't ever do anything.
- No. But they could do real harm to themselves or others.
- I think we should take control. It's always about them.
- How do you propose to do that?
[...]