This is how I imagine them:
Stargazer (father) is a famous astrologer and astronomer who has dedicated his entire life to the study of the cosmos. Lily (mother) is a pony from a wealthy family, a dreamer who loves night walks through the forest. They met just at one of these walks, when Stargazer looked at the constellation through a telescope in the forest, and Lily accidentally stumbled upon him and decided to join.