Escape to Witch Mountain (1975)

Revealing mistake: You can see the wires on the handgun pointed at the two extraterrestrial children when the bad guys are staring in shock at the "floating gun."

Tricia Webster

Store Clerk: Well, sir, a covered wagon pulling outta St. Joe didn't take near as much supplies as you got yourself here, Mr. O'Day.
Jason O'Day: You're sure one well-informed man, aren't ya? Now, did you think you can hand me that carton without straining yourself, or are you just tuckered out from sticking your nose in my affairs?

Bishop73