Phineas and Ferb Song - Where Did We Go Wrong?

The song "Where Did We Go Wrong" from the Phineas and Ferb episode "Phineas and Ferb's Christmas Vacation."

Lyrics:
How could we be naughty when I'd thought we'd been so nice?
Could we have been blinded to some little hidden vice?
Did our visions of sugar plums not dance like they should?
I'm racking my brain here, I really thought we were good.

I know you've got that list and I know you check it twice.
But could you check it again?
'Cause it seems to me we were all pretty nice.
(All except for Buford, 'cause he's got that whole last-minute reprieve theory.)
(It's gonna work! You watch!)

Where did we go wrong?
Please tell me!
Where did we go wrong?
Where did we go...
Won't somebody tell me?
Where did we go wrong?