Dave Coulier shared an uplifting message on social media in the middle of his chemotherapy treatment on Friday, just days after Full house the star revealed earlier this week that he had been diagnosed with stage 3 non-Hodgkin lymphoma.

“Putting a positive spin and sending love to all of you fighting and going through chemo,” Coulier wrote on his Instagram story, accompanied by a photo of him giving a thumbs up while sitting in a hospital room. “And remember to laugh.”

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Coulier played Joey on full house, best friend of main character Danny Tanner, who was played by the late Bob Saget. Coulier reprized his role as Joey in Fuller House, the Full house sequel that aired for five seasons on Netflix. Coulier revealed his cancer diagnosis during an interview on Show today On Wednesday, he said that a month before he was diagnosed, he had felt sick and noticed a swollen lymph node in his groin. His doctor removed the lump and did a biopsy, which revealed the lymphoma.

“The first thing I said to them was, ‘Wait a minute — cancer?'” Coulier said in it Show today interview. “(I felt) like I got punched in the gut because that never happens to you. You always hear it’s happening to someone else.”

Among those who publicly shared support for Coulier were his previous Full house costar John Stamos, who shared several pictures and videos of the two on his Instagram account. “My brother from day 1,” Stamos wrote. “Love you @dcoulier and I will be by your side through it all.”

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