The 59-year-old author was spotted with the 21-year-old model and 22-year-old singer at Laurel Hardware restaurant Friday. An eyewitness told E! News Shriver appeared to have a good time with her son and his girlfriend.
"They all looked like they were having a great time," the source revealed. "Enjoying engaging conversation and laughing. It looked like Maria and Miley got along really well ... Miley and Patrick were really cute together. They look like they are genuinely in love."
Shriver cheered on the New England Patriots in Superbowl XLIX on Sunday, while Schwarzenegger and Cyrus enjoyed breakfast in bed. The model tweeted his appreciation, writing, "When yoooo GF brings you eggs, oatmeal, toast and coffee to bed. Ohhhhhh I'm lucky."
Schwarzenegger and Cyrus have been linked since November 2014, and Shriver is reportedly "happy" about the relationship. The singer also won over her beau's extended family, making a good impression on his uncle, Anthony Shriver, at Art Basel in December.