We must be more careful.
2 seconds sound clip from the Harvey (1950) movie soundboard.
You can hear this line at 00:08:25.647 in the Blu-ray version of the movie.
Quote context
[...]
- Hurry now and stick with him all afternoon. Quickly, boy. Quickly.
- Oh! The doctor will see you in a minute.
- Afternoon, Mr. Cracker. Excuse me.
- Oh, he's just fine, fine. How are you?
- Is this all right? You sure? Hmm? All right. Give you a hand there. Whoop! Don't slip! There.
[...]