Kate Hudson brings son Ryder Robinson, 20, as her date to fashion show in Italy

This celebrity kid is keeping it casual.

Kate Hudson brought her 20-year-old son, Ryder Robinson, to Max Mara’s fashion show in Venice, Italy Tuesday, for a rare mother/son outing.

While the “Almost Famous” star, 45, graced the front row with a plunging black shirtdress, her son rocked black Birkenstock clogs ($160) with a white T-shirt as they enjoyed the glamorous runway presentation.

Although Robinson — who Hudson shares with ex-husband, Black Crowes singer Chris Robinson — went for a laid-back look, he coordinated with his mom in black trousers and a black-and-white checkered shirt worn open over his tee.

The actress, 45, wore her maxi dress — which featured dramatic wide sleeves and a high slit — belted at the waist, adding black heels with a strap across the front.

The “How to Lose a Guy in 10 Days” star added bold turquoise drop earrings to her outfit, rocking a bright red lip and beachy waves in her hair.

Ryder and mom sat next to Brie Larson, Yara Shahidi and Italian actress Miriam Leone in the front row as Max Mara presented its latest collection at the historic Palazzo Ducale in Venice.

And while Ryder got the green light to attend the fashion show, Hudson made her Italian trip a family affair, posting photos and videos of her children and fiancé Danny Fujikawa’s birthday in the city.

The mom of three — who also shares son Bingham, 12, with former fiancé Matt Bellamy, 46, and daughter Rani, 5, with her Fujikawa, 38 — recently opened up about her “whirlwind” first marriage on the “Call Her Daddy” podcast.

Although she married Ryder’s dad at age 21 after a short courtship, Hudson said she “didn’t question it for a second.”

“We were so connected. And Chris taught me so much about love, connection. It was just a wonderfully passionate relationship,” the star added.