To prevent future toddler agony, do not let them lose their puzzle pieces. That’s easier said than done — how are you even supposed to store those clunky things with multiple loose parts?
You can buy a wire puzzle rack, which may be a good option if you have about a dozen puzzles, but if you only own a few and want to keep them on a shelf or in a bin, a solution is to keep them in clear poly envelopes.
I saw the idea on Pinterest and thought it was great. Chunky toddler puzzle boards fit snugly into legal size envelopes, and will stay intact even when shifted around. To make it even easier for little kids to get to their puzzles, you can replace the string clasps with Velcro circles.
Now your toddler won’t experience that universally infuriating moment of being almost done with a puzzle only to discover that the final piece is missing. Don’t worry, though — they’ll still have plenty of other reasons to cry.