Katherine Schwarzenegger held a small bridal shower Saturday, to which only those closest to her were invited, People magazine reports.
The intimate party was held at her mom Maria Shriver's home, where Oprah Winfrey was among the guests. A source told People the site was decorated with "lots of white flowers and candles," and was filled with live music.
Katherine wore a long, white dress and had her hair down, pulled to the side with a matching white clip.
As the day wound down, Katherine's dad, Arnold Schwarzenegger, popped in; he had been attending his son Joseph Baena's college commencement.
Her husband-to-be Chris Pratt also showed up later in the day.
Pratt, 39, and Schwarzenegger, 29, have been together since the summer, and engaged since January.