Robin Williams' oldest son, Zachary, spoke out for the first time since his father's death at a charity event held Thursday in New York City.

The 31-year-old attended the Christopher and Dana Reeve Foundation's fundraising gala, and discussed how he and his family are coping with his the tremendous loss.

"We're doing okay," Zak told ET. "We're working hard to build our strength and acclimating to the new normal.

"A large part of what we're doing through this grieving process is giving and spending time focusing on others."

Robin Williams and Christopher Reeve attended the Julliard School together, and remained friends until Reeve's death in 2004. The Christopher and Dana Reeve Foundation funds spinal cord injury research, and provides grants and resources for those living with paralysis.

Williams committed suicide on August 11, and innumerable fans across the globe expressed sadness and prayers for his family. Zak said the amount of support shown was incredible.

"The outpouring was remarkable," he admitted. "People shared their supportive words, art, and all sorts of amazing tributes to my father."

Williams' daughter, Zelda, paid tribute to her late father by getting a series of tattoos last month.

The 25-year-old got a hummingbird tattooed on her right hand between her wrist and her thumb, and her father's birthday, "7.21.51.," tattooed on her inside wrist.

"For poppo," she captioned the black-and-white photograph. "Thank you to the incomparable @dr_woo_ssc for so beautifully bringing my reminders to life. I'll always put my hand out to shake with a smile."

Dr. Woo is a celebrity tattoo artist in Los Angeles who has inked Drake, Zoë Kravitz and David Beckham.

Shortly after her father's death, Zelda deleted her social media accounts due to cruel comments. She returned to Twitter and Facebook less than a month later, pledging that she would not be bullied into silence.

Williams has a younger son, Cody, who is 22 years old.