The song is from season 3 episode 13 of MLP:FiM.
♫ Lyrics for the song:
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[Rainbow Dash]
These animals don't listen, no, not one little bit
They run around out of control and throw their hissy fits
It's up to me to stop them, 'cause plainly you can see
It's got to be my destiny, and it's what my cutie mark is telling me
[Fluttershy]
I try to keep them laughing, put a smile upon their face
But no matter what I try, it seems a bit of a disgrace
I have to entertain them, it's there for all to see
It's got to be my destiny, and it's what my cutie mark is telling me
[Pinkie Pie]
I don't care much for pickin' fruit and plowin' fields ain't such a hoot
No matter what I try, I cannot fix this busted water chute!
I've got so many chores to do, it's no fun being me
But it has to be my destiny, 'cause it's what my cutie mark is telling me
[Applejack]
Lookie here at what I made, I think that it's a dress
I know it doesn't look like much, I'm under some distress
Could y'all give me a hand here and help me fix this mess?
My destiny is not pretty, but it's what my cutie mark is tellin' me
[Rarity]
I'm in love with weather patterns but the others have concerns
For I just gave them frostbite over-top of their sunburns
I have to keep on trying for everyone can see
It's got to be
[Fluttershy]
It's got to be
[Pinkie Pie]
My destiny
[Applejack]
My destiny
[Rarity, Rainbow Dash, and Fluttershy]
And it's what my cutie mark
[Pinkie Pie and Applejack]
It's what my cutie mark
[All except Twilight]
Yes, it's what my cutie mark is telling me!
