There's nothing to be afraid of. All you have to do is go to sleep and rest.
9 seconds sound clip from the The Best Years of Our Lives (1946) movie soundboard.
You can hear this line at 00:52:31.799 in the Blu-ray version of the movie.
Quote context
[...]
- Come on, the rest of you guys. Come on, get out!
- Wake up.
- Gadorsky! She's burning up! Get out! Get out!
- She's burning up! She's gonna hit. Look out!
- It's all right, Fred. Go back to sleep. Go back to sleep. Go back to sleep, Fred.
- There's nothing to be afraid of. All you have to do is go to sleep and rest.
- Go to sleep. Go to sleep, Fred. Go to sleep and rest.
- Oh, I'm terribly sorry I woke you up.
- Oh, that's all right, but...
[...]