Days after the Full House alum shared that he was diagnosed with stage 3 Non-Hodgkin's lymphoma, John was there to help his former costar embrace the next step of his cancer journey: shaving his head. And of course, Uncle Jesse even said goodbye to his own famous locks—well, sort of.
"Nothing like throwing on a bald cap and flexing some Photoshop skills to show some love and solidarity with my bro @dcoulier," John shared to Instagram Nov. 18, alongside photos of shaving Dave's head. "You're handling this with so much strength and positivity—it's inspiring."
The 61-year-old added, "I know you're going to get through this, and I'm proud to stand with you every step of the way. I love you."
John also gave a special shoutout to Dave's wife of four years Melissa Coulier, writing that she "is the most wonderfulest—your true life line!"
John and Dave have had an incredibly close relationship since they starred on the hit '90s sitcom, with John showing his support for Dave after he shared his diagnosis.
"My brother from day 1," he wrote on Instagram Nov. 13, alongside a photo carousel of the two over the years. "Love you @dcoulier and I'll be by your side through it all."
Instagram/John Stamos
Dave previously explained that his cancer battle has been a fast and furious one, as he learned about the development in his lymph nodes just five weeks prior to sharing the news publicly.
"In that time, I've had three surgeries, I've had chemo, I've lost a little bit of hair," he told Today's Hoda Kotb on Nov. 13. "I kind of look like a little baby bird now, but it has been a roller coaster ride for sure."
The 65-year-old explained that he was dealing with "a very aggressive type of lymphoma," and because it happened so quickly, he began treatments for chemotherapy right away.
For now, he's focusing on the good news, which is that the cancer has not spread.
Kelly Lee Barrett/Getty Images
"At that point, the curability rate went up to 90 plus percent," he continued. "So it's very treatable."
"I told Melissa I don't know why, but I [am] OK with whatever the news [is] going to be no matter how devastating," he told Today.com. "I can't explain where that came from. I've had an incredible life. I've had the most amazing people in my life. This has been an extraordinary journey, and I'm OK if this is the end of the journey."
To see more stars who have discussed their cancer diagnoses, keep reading.