Ryan Gosling Wears T-Shirt with Eva Mendes’ Book Title During UK Press Tour

Ryan Gosling is supporting Eva Mendes in the cutest way possible!

As the Barbie star, 43, is currently promoting his next film The Fall Guy overseas with Emily Blunt, he’s keeping his partner, 50, near and dear to his heart.

On Monday, April 29, Hits Radio shared a video interview of the costars to the station’s YouTube account. 

In the clip, Gosling is seen wearing a T-shirt that reads, "Desi, Mami, and the Never-Ending Worries” — which happens to be the title of Mendes’ debut children’s book, out later this fall. 

"Desi, Mami and the Never-Ending Worries is a love letter to my kids and yours,” the Hitch actress told PEOPLE exclusively in February.

Gosling and Mendes, who have been together since 2011, are parents to two daughters: Esmeralda, 9, and Amada, 8. 

“Learning how to train our brain to work for us and not against us is easier said than done! At my home and in Desi's, we try to deal with the never-ending worries and anxieties that we all have, so those negative thoughts don’t take over and dominate,” she continued.

The book hits shelves on Sept. 17 and will be available in both English and Spanish.

Mendes has previously explained why although she and Gosling have been together for more than a decade, they do not do red carpets together and are rarely seen side by side at other Hollywood events.

Last April, she shared a clip on Instagram of a scene from 2012's The Place Beyond the Pines — a film in which she and Gosling costarred. 

In her caption, she noted that the crime thriller was not their first time meeting. 

While responding to commenters, Mendes said she’s "only comfortable posting" images with Gosling that are already publicly available.

One user made mention of how they would love to see the pair at Barbie events, to which the actress responded, "What a cool comment, thank you. But we don't do those things together."

In early March, a source shared with PEOPLE their take on the couple’s longevity. 

“It truly seems they are surviving Hollywood as a couple, because of the way they‘ve handled being famous. They try their best to stay out of the spotlight," the insider said. 

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"For them, the most important job is their girls. Everything else comes second," the source continued. 

As far as major events, such as this year’s Academy Awards, which Mendes was not present for, the insider added: "Of course, Eva is proud and excited for Ryan. She still sees it as a job though."

The Fall Guy arrives in theaters on Friday, May 3.