Biblical or Religious Concepts
This feels like a strong start, as 'Sheep', 'Stars', and 'Blessings' are all common biblical motifs. However, the theory falls apart completely with 'Calories' and 'Votes', which are secular, modern concepts with no clear connection to the theme.
Words in Songs or Nursery Rhymes
This is another plausible guess, as phrases like 'little sheep' or 'twinkle, twinkle, little star' come to mind. The theme breaks on 'Blessings', 'Calories', and 'Votes', which are not common core components of songs or rhymes.
Things Found on a Farm
One might latch onto 'Sheep' and try to build a theme from there, but 'Stars', 'Blessings', 'Calories', and 'Votes' have no direct relationship to a farm environment. This theme fails on four of the five clues.