What do the moon and sun have in common

They are locked together in stable orbits due to gravity - All have gravity - All of them are in the Milky Way - The Moon orbits the Earth, the Earth orbits the Sun - Because they appear to be the same size in the sky, the Sun, Earth and Moon work together to create eclipses - Earth depends on both the Sun and the moon for life as humans know it to exist.

their both stars