John Stamos is addressing negativity surrounding his bald cap photo tribute to Dave Coulier after his former 'Full House' costar was diagnosed with cancer.

The "Full House" alum revealed Thursday that he wasn't able to shave his head because he's filming a new project soon — and said the criticism "really hurt me."

Dave Coulier, who has an "aggressive" form of Non-Hodgkin lymphoma, said he "laughed out loud" when he saw his "Full House" co-star in a bald cap.

Actor Dave Coulier is speaking out after his longtime friend and former co-star John Stamos received backlash for wearing a bald cap while shaving Coulier’s head. This month, the “Full House” stars got together to share a few laughs after Coulier publicly revealed his Stage 3 non-Hodgkin lymphoma diagnosis.

Now, on Instagram, his “Full House” co-star John Stamos shared images of the lifelong friends together. Stamos was wearing a bald cap and shaving Coulier’s head. “Nothing like throwing on a bald cap and flexing some Photoshop skills to show some love and solidarity with my bro, Dave Coulier,” Stamos wrote.

Dave Coulier and John Stamos have a long history. The two spent years filming the beloved series Full House together, but their friendship did not end there. After the 65-year-old revealed he was diagnosed with stage 3 Non-Hodgkin lymphoma,

Earlier this month, the Full House actor - known for playing Joey Gladstone on the sitcom, revealed he had been diagnosed with a "very aggressive" form of non-Hodgkin lymphoma and was undergoing chemotherapy treatments.

John Stamos defended his actions after facing backlash for wearing a bald cap to show support for fellow “Full House” star Dave Coulier, amid his cancer battle. The internet attacked the famous actor when he shared Instagram posts of himself shaving Coulier’s head,