Robin Williams’ Son Zak Honors His Father on 9th Anniversary of Actor’s Death: ‘These Days Are Always Hard’

Robin Williams’ son Zak is paying tribute to his father.

On Friday, the 40-year-old shared a poignant post along with a photo of the late actor on Instagram as he remembered his father on the ninth anniversary of his death.

“Dad, on the 9th anniversary of your passing, I’m remembering you for your most excellent fashion choices,” Zak wrote in his caption. In the photo he shared, Robin was seen on a tennis court holding up a tennis racket while wearing a printed T-shirt and baggy cargo shorts.

 “These days are always hard and I love remembering you for being so very, very YOU,” he continued. “Love you so much!”

Robin died by suicide at the age of 63 on Aug. 11, 2014. His representative shared with PEOPLE after his death that “he had been battling severe depression of late.” It was later discovered the actor had Lewy body dementia, the second-most common type of progressive dementia after Alzheimer’s disease.

The ninth anniversary of Robin’s death comes after his children celebrated what would have been his 72nd birthday last month with posts on social media.

“Happy 72nd Dad! Was remembering how much I used to love that look you’d give. That look with a mischievous, loving grin that your friends and loved ones knew so well. Joyous and curious and wondrous,” Zak captioned the Instagram post alongside a photo that showed his father wearing headphones and smiling.

“Miss you and love you forever!” he added.

Robin’s daughter Zelda Williams tweeted at the time about how she believed Robin would have supported the current writers and actor’s strike as she posted a photo of the late actor joining the New York picket line in the 2007 strike.

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“Happy birthday to Poppo, who definitely would’ve been out there fighting the good fight for art and artists today and always,” the 34-year-old wrote in her caption.

The Jumanji star had been an advocate of screenwriters’ rights and discussed his views with The Hollywood Reporter during the protests at the time. “This is not about millionaire screenwriters. They don’t need to be on strike. This is not about me, I’m fine,” Robbins said to the outlet. “This is about a large amount of people who are simply trying to get their fair share.”

Zak is the eldest son of Robin and the actor’s first wife Valerie Velardi. Zelda and brother Cody Williams, 31, are children from Robin’s second marriage to Marsha Garces Williams.