Once In A Blue Moon is a song sung by by Papa Smurf and Dreamy at the end of the episode with the same name that introduced Baby Smurf.
- Dreamy: Once in a blue moon a baby comes to stay
- Papa Smurf: Once in a blue moon, your heart is smurfed away
- Both: And once in a blue moon, your heart is filled with love
- Dreamy: And all the things...
- Papa Smurf: ...a baby brings...
- Both: from somewhere up above [gentle laughter]
- In the French and Arabic versions of the Smurfs cartoon show, Papa Smurf sings the song alone without laughter at the end.
- In the 2006 Polish re-dub, Papa Smurf and Dreamy's lines are accompanied with a background chorus.
- The German dub has the song left in English.
- In the Spanish version, Papa Smurf sings the first two lyrics, and then the rest of the song is spoken, followed by gentle laughter from all of the Smurfs.
- In the Italian version, the song is spoken by a female narrator.
- In the Hebrew version, the song is sung by a woman (the same actress who does the Hebrew narration and lyrics for the intro sequence) and the Smurfs' gentle laughter is not heard.