I think we are mostly our moon signs as babies and toddlers until around age 6 or 7 and then we become more motivated to express our ego, standard traits of the sun. Our sun is who we were told we ought to be. Say you’re a Libra sun with a Leo moon…your true mode below the surface needs praise and adoration but you were likely told to be more interested in others and sharing. Or you’re a Taurus moon with a Virgo sun. You were told growing out of the baby years to be less lazy, less sleepy and less messy so you consciously chose and learned to be more structured and organized. Or perhaps, your moon sign was the nervous and self-critical Virgo moon and your parents observing this in their young child wanted you to be more confident and visionary, leading to a Sag sun.
And although your sun sign has “duped” you into thinking that identity is who you are, it also a part you learned to play so well and it was not always a natural expression. The moon is the true natural expression of the nameless, emotional self. But if you look at old pictures of yourself as a toddler or recall yourself at age 5 or younger, however you can, you will be looking at your moon sign completely embodied. It’s an interesting perspective to realize when looking at your early, early childhood memories. It’s how you are when you’re not trying to impress anyone or take on an important role or assert any identity (or rather it CAN be if you’re a Leo or Aries moon). It’s how you just /are/, the essence of your being. The ability to be in touch with the feminine principle, the self-soothing understanding of ourselves is very important to success and happiness in life. Your moon comes out when you relax into your being just as the literal moon comes out when we stop hustling and bustling and instead lay down to dream on our true thoughts and desires and fantasies.