End of a nursery rhyme, or the fate of this puzzle's other three long answers

Question:

Answer:

ALLFALLDOWN

Length:

Similar Crossword Questions:

Nursery rhyme line that finishes this puzzle's theme
Each of this puzzle's long Across answers sounds like one
It uses only the 12 letters A, E, H, I, K, L, M, N, O, P, U and W (like eight long answers in this puzzle)
Speak derisively, and a hint to how this puzzle's long answers were created
Show since 12/17/1989 whose five main family members are hidden in this puzzle's other long across answers
Brief version of this puzzle's title hidden in eight long puzzle answers
State short forms strung together in 12 long answers in this puzzle
List shortener hidden in eight long puzzle answers
Provide recon, and another hint to this puzzle's long answers
Phrase whose abbreviation is the key to four long puzzle answers
Main thoroughfare in Manhattan (one can be found in each of the four long answers in this puzzle)
Puzzle title people hidden in eight long answers
What each of the four long answers in this puzzle is
Rhyme runaway, and how this puzzle's theme answers are formed?
Reservoir, and hint to puzzle theme found in seven long answers
Sweet, or, read another way, a hint to five long puzzle answers
Puzzle honoree found in eight long answers
This weekend's fridge contents, probably, and what's missing from five long puzzle answers?
Movie good guys responsible for the circled squares in eight long puzzle answers
What the puzzle's long answers all were
Big bank held by this puzzle's long answers
Business term found in eight long puzzle answers
They're hidden in seven long answers in this puzzle
What this puzzle's long answers each have three of
Feature of six other long answers in this puzzle