The 21-year-old enjoyed date night on Friday with boyfriend Owen Mahoney as they watched the San Francisco Giants triumph over the Houston Astros, 8-6, at Oracle Park.
"He's a Giants fan…and I'm a garlic fries fan," Phillippe wrote on Instagram, posting a selfie from their seats with her beau wearing a Giants jersey over his hoodie.
She and Mahoney recently joined her brother Deacon Phillippe, 17, and his girlfriend Marine Degryse for a group photo during a tropical getaway with the family. "Hehe good times," Ava commented on photos from the trip.
Ava previously posted a sunset photo in Austin, Texas, with her beau, whom she met at UC Berkeley and has been dating since at least 2019. Witherspoon, 45, gave her seal of approval in the comments section. "These two," she wrote, along with a heart eye emoji.
Witherspoon was married to Ryan Phillippe, 46, from 1999 to 2008 after they met on the set of Cruel Intentions. She later tied the knot in 2011 with Jim Toth, 51, with whom she shares 8-year-old son Tennessee James.
The Legally Blonde star recently opened up about watching her children get older. "That makes me want to cry, the idea of having a long relationship with adult children," she told Tracee Ellis Ross in June for Interview.
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"I never expected the kind of relationship that I have with them, but it's so rewarding to be able to have kids that you can process life with a little bit, and they help me understand the complexities of what it means to be a human now," the proud mom explained. "So I'm really, really grateful that these little humans are in my life. Adult humans. I have two adult children now, Tracee. It's crazy."
The feeling is mutual, as Witherspoon's kids previously expressed their love for her on Mother's Day. "To my best friend, role model, cheerleader, confidante, and so much more: Happy Mother's Day!" Ava wrote on Instagram.