Who said "Perhaps they need a lesson in mortality."?

This quote is attributed to Jack Skellington.

Perhaps they need a lesson in mortality. - Jack Skellington

"Perhaps they need a lesson in mortality."

Jack Skellington Death

"I am the Pumpkin King!"

"How wonderful! How strange! Oh, how I love it so!"

"There's something kind of funny about the whole thing."

"I've grown so weary of the same old thing."

"Death doesn't scare me anymore."

"Death and I are old friends."

"Welcome to my world."

"Death is just the beginning."