John Stamos Wears Bald Cap in ‘Solidarity’ After ‘Bro’ Dave Coulier’s Cancer Diagnosis: ‘Going to Get Through This’

John Stamos is showing his support for Dave Coulier amid his cancer diagnosis. 

In new photos shared to Instagram on Monday, Nov. 18, the Full House co-stars posted a joint carousel with a special message.

“Nothing like throwing on a bald cap and flexing some Photoshop skills to show some love and solidarity with my bro @dcoulier,” Stamos, 61, began as the caption to the three-photo roundup. 

“You’re handling this with so much strength and positivity—it’s inspiring. I know you’re going to get through this, and I’m proud to stand with you every step of the way,” Stamos continued, noting that Coulier’s wife Melissa “is the most wonderfulest.”

The first image showed the former costars and longtime friends posing — Coulier, 65, with his head shaved, and Stamos wearing a baldcap in solidarity.

For the second swipe, Stamos laughed with Coulier while helping him to shave his head. The final photo showed Stamos and Melissa both kissing Coulier’s bald head. 

Coulier revealed his stage 3 non-Hodgkin lymphoma diagnosis exclusively to PEOPLE on Nov. 13.

He learned of his cancer after an upper respiratory infection in October resulted in his lymph nodes swelling quickly, with one area growing to the size of a golf ball. The growth led to Coulier undergoing PET and CT scans and a biopsy at the suggestion of his doctors.

“Three days later, my doctors called me back and they said, ‘We wish we had better news for you, but you have non-Hodgkin’s lymphoma and it’s called B cell and it’s very aggressive,’ ” he said. 

“I went from, I got a little bit of a head cold to I have cancer, and it was pretty overwhelming,” Coulier told PEOPLE. “This has been a really fast roller coaster ride of a journey.” 

After receiving the news, he shared the information with his Full House family — including Stamos, Candace Cameron Bure, Andrea Barber, Jodie Sweetin, Lori Loughlin, Scott Weinger and series creator Jeff Franklin. 

“I didn’t want them to hear it from someone else, so I sent a text message out,” the actor said, noting that the response from everyone “was immediate.”

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“It was just this outpouring of, ‘I will be there. You just name the time, and I know you’re in great hands with Mel, but what can we do?’ It really is overwhelming the love that we have for each other. We’ve been there for so many years for each other and it’s pretty remarkable.” 

Hours after Dave’s interview with PEOPLE was published, Stamos posted a message to social media, promising his friend that he would “be by your side through it all.”