Near the end, when Pocoyo appears from the left using the broom as a guitar to clean the first time, you can see part of a blue block appearing on the right extreme during a single frame in 16:9 version. Narrator is saying "Pocoyo, I'm sorry but this is no time for..." and appears in "but". You can check it at frame 7941 (5:17.640 s) in youtube video KTdeultiqxA.