London: Oscar-winning actor Robin Williams' eldest son Zak is still mourning his loss, a year after the funnyman committed suicide.

Robin Williams
Robin Williams. Pic/Santa Banta 

Zack, 32, revealed he is trying "to focus on the joyful moments and memories," reported Female First.

"We try to focus on the joyful moments and memories. We're still grieving. We're moving through the process of healing and recovering," said Zak.

He celebrated what would have been his father's 64th birthday on Tuesday along with his siblings Zelda, 25, and Cody, 23, as well as other relatives by having a private dinner, and said they have been helped by "wonderful family and friends" during the 11 months since Robin's passing.