Zipp is the only one in the Mane 5 (plus Sprout) who didn’t sing at all thus far.

Even in Make Your Mark where Zipp was the central character, she didn’t get her own song while her sister did. In Izzy’s Fit Right In, I recall Zipp dancing but never singing (correct me if I’m wrong). By contrast, in G4 all the Mane 6 sang together right from the get go (see: At the Gala, Winter Wrap Up). Main characters in pony shows sing. That’s just what they do. Zipp seems to be the exception.

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