Get Sprite's Position in Atlas

I need to be able to grab the positioning of a specific sprite in a sprite atlas. Since calling sprite.texture returns the sprite atlas if its been packed, I thought I would be able to get this information from sprite.textureRectOffset, however that seems like its returning an offset of zero even for sprites that I know are definitely offset in the atlas. This is odd to me since the sprites don't have a mesh type of FullRect but maybe I'm missing something with how that textureRectOffset parameter works.

Does anyone know if there is a way to grab or calculate the positioning of a sprite's rect in a sprite atlas?