You saw it happen!
3 seconds sound clip from the Frosty the Snowman (1969) movie soundboard.
You can hear this line at 00:04:19 in the Blu-ray version of the movie.
Quote context
[...]
- If that hat is magic, I want it back.
- But it's not yours anymore! You threw it away!
- Don't talk back to your elders, you naughty naughty little girl.
- And you, stay in there, or there will be no carrots for Christmas.
- But you can't take that hat back, it brought Frosty to life.
- Quiet, I can't lose that hat if it's really got magic now! It'll make me a billionaire magician!
- But we saw Frosty come to life, didn't we?
- You silly children believe everything you see.
- When you're grown up you'll realize that snowmen can't come to life.
[...]