Who said "I won't let you down."?

This quote is attributed to Flounder.

I won't let you down. - Flounder

"I won't let you down."

Flounder

"I'm scared, Ariel!"

"Don't you think you're being just a little bit too reckless?"

"I can't do this. I'm too young to die!"

"You really shouldn't have done that."