George Stephanopoulos rarely posts on social media, but made the exception this weekend - and for a very special reason.
Sharing a rare photo of himself with his daughter on the special day, George penned: "Happy graduation day to my youngest," alongside a heart emoji.
George's wife, Ali Wentworth, was equally proud, sharing several photos from the big day on her own Instagram page.
She wrote: "The baby daughter is launched! A perpetually optimistic, joyful, generous, empathetic, fun-loving, and wise human is spreading her wings! Bursting with love and pride! P.S. You know she is my daughter because she ran out after she graduated and got an ice cream cone across the street."
George's GMA co-stars, including Robin Roberts, Michael Strahan and Ginger Zee all shared messages of support following Harper's achievement. "Congratulations!!" Michael wrote, alongside a clapping hand emoji, while Robin penned: "Soo sweet. Congrats to your lovely baby girl." Ginger simply responded with a love heart emoji.
Fans also sent messages to the family. "Congratulations to her! It takes a lot of hard work to make it to this point, and she (plus Mom and Dad!) should be very proud!," one wrote, while another remarked: "Congratulations Harper, watch out world!"
The teenager is now set to embark on a new chapter of her life come September, when she moves home to attend college. Harper moving out of the family home will see George and Ali becoming empty nesters too.
The couple's firstborn, Elliott, 20, left home in 2021 to study, and at the time, Ali admitted that she was incredibly emotional about the bittersweet milestone.
Luckily, the 20-year-old often comes back to visit her family, and was recently pictured on the red carpet with her famous parents and sister, at the Pretty Baby premiere in New York City - which was produced by George and Ali's production company.
Elliott and Harper both have strong bonds with their parents, with Ali sharing an insight into their relationship in the past. Chatting to Harry Connick Jr, she said: "I have two girls. George is the only guy in the house. For some reason, he gets beat up constantly. He is always wrong. He is an idiot. He is a loser, but in a loving way."
The Go Ask Ali podcast star often shares hilarious stories about their family life in interviews, from their home life with their daughters to their relationship.
Speaking to HELLO! at the 33rd Annual Colleagues Spring Luncheon and Oscar de la Renta Fashion Show on Tuesday April 25, Ali even joked that she doesn't want her husband as a guest, quipping: "I am not sure what we would talk about!"
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