- But why?
- I don't know, Sarah. I don't know.

4 seconds sound clip from the 'Twas the Night Before Christmas (1974) movie soundboard.

You can hear this line at 00:02:00.296 in the Blu-ray version of the movie.

Quote context

[...]

- As we say when approaching a tall piece of cheddar, better start from the top.

- The trouble began two months ago when the mailman came.

- Hey, wait a minute, this isn't for us. It's for Santa.

- So is this.

- And this.

- And this.

- I spilled that ink. These are the letters we wrote to Santa.

- The letters we wrote to Santa, returned?

- Not accepted by addressee.

- What does that mean, Father?

- That Santa doesn't want our letters.

- But why?

- I don't know, Sarah. I don't know.

- The same thing was happening all over town as boys and girls got their letters back from Santa.

- No one knew what it meant. But we, grownups, knew one thing for sure: We were gonna do everything we could to find out.

- 'Twas the night before Christmas, when all through the house, not a creature was stirring, not even a mouse. (2)

- Come on, old Kris Kringle, down the Milky Way. Santa, we need you today.

[...]