Moonshine joined the pack during the Total Lunar Eclipse. She was surrounded by many lunar lights and had an abnormal aura which pulled the leader - Aphelios - close. He realized that she had been trapped in what seemed like a human-made trap.
Even though Moon does not remember much of her past, what is known is, that she has a connection to the Dreamlands and while she hopes to remember more someday, she plans to stay with this clan for as long as possible.