Leah is a horse, and apparently Bo's love interest, in The Star.
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also found with Edith and Zach
These animals are anything but stable
Residents of the most famous stable in history who haven't been able to sleep for nine months - ever - since that star appeared in the sky. Zach the Goat is nervous and paranoid, Edith the Cow is cool and just wants some peace, and Leah the Horse thinks the beauty of the spotlight is worth missing some sleep.