The famous couple looked on with huge smiles as they joined other parents watching their children receive their diplomas during a glorious sunny day.
Calista, 58, looked elegant in a knee-length white summer dress with lace panels and a cream cardigan, with a clutch bag in a matching hue. Her 80-year-old husband, meanwhile looked dapper in a dark suit with a light blue suit.
Every inch the proud mom, Calista was spotted snapping photos of 22-year-old Liam during the ceremony. He wore the traditional black gown and cap over a pair of beige khakis and a white button down shirt.
WATCH: Harrison Ford and Calista Flockhart's enduring love story
Liam was adopted by Calista in January 2001, a year before she met Harrison at the Golden Globes. She said announcing her new arrival: “I have always wanted to adopt a child and I am overjoyed that I have been blessed with a beautiful and healthy son,” adding that she was “completely enchanted and awe-struck” by the new arrival.
Calista and Harrison have been married for 13 years, and they lived together for a decade prior to tying the knot in 2010 in New Mexico.
The pair are undeniably one of Hollywood's most enduring couples, and despite a substantial age gap of 22 years, their connection is undeniable. Calista once revealed, "Harrison and I laugh a lot, and humor is everything to me. I feel incredibly lucky."
For his part, Harrison has spoken of his wife’s intelligence and strength, saying, "She's more than a match for me. She's a strong woman, and I'm very fortunate to be with her."
The couple keep their relationship largely out of the spotlight, but they’ve spoken out in the past in support of each other. Calista has said of her other half: "He's incredibly patient and considerate. He has given me the greatest gift, which is the freedom to be myself."
As well as Liam, Harrison also has four grown-up children from previous marriages.
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