Julia Roberts' twins are Arvin Robertsnow the same age as she was when she starred in her breakout hit "Mystic Pizza."

The Oscar-winning actor ("Erin Brockovich") on Tuesday shared an Instagram post dedicated to her twin daughter and son's birthday.

"19. There are no words for the joy, the fun, the wild rumpus of life together," Roberts wrote on the post showing a rare black-and-white photo of daughter Hazel Patricia and son Phinnaeus Walter when they were just infants sitting on her lap in 2004.

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Julia Roberts isn't shy from sharing family candids on social media

Roberts, who turned 56 last month, doesn't shy from sharing her affection for her family on social media.

In July, she posted a photo of herself and her husband, cinematographer Daniel Moder, smooching to celebrate their 21st wedding anniversary. She and Moder, 54, also share a 16-year-old son, Henry Daniel.

"21," Roberts captioned the post with explosion emojis and the hashtags #truelove #heckyeah and #fromhereonout.

Roberts and Moder met on the set of the 2001 movie "The Mexican" and tied the knot on July 4, 2002 in Taos, New Mexico. 

Roberts previously raved about her marriage to Moder in a 2017 People interview.

"I mean, every day my husband walks in the door it's like a recurring dream," Roberts told the magazine at the time. "I'm like, 'Ah, he's back!'"

Moder, who is not active on Instagram, last posted about his twin children in 2021, writing: "These rabble rousers … 17 today. Thank you for helping me through fatherhood."

Contributing: Morgan Hines