Why does my sister not attend parties?

Name: RheaDate of Birth: 6th June 2000Place of Birth: PuneTime of Birth: 5:15 PM

My sister does not need to go to parties or social events. She turns to be silent and nervous and uneasy, even with her family. It's hard to see her struggle. Her Moon or Rahu-Ketu placements may have a tendency of her being sensitive to social energy, I believe. I also hope that astrology will help her to feel comfortable and brave in social contexts.