Robin Williams' daughter Zelda honors her father on World Mental Health Day

Zelda Williams honored her late father, Oscar-winning actor Robin Williams, on World Mental Health Day last Friday.

The 25-year-old actress praised her father, who passed away in August, for "openly fighting" with depression and encouraging others to "fight on" against mental illness.

"Today is #WorldMentalHealthDay," Zelda wrote on Twitter. "Mental illness is often misunderstood and misrepresented, but that's starting to change. Let's end the stigma."

"Mental health IS as important as physical health and whether there are visible signs or not, the suffering is real," she added. "It can affect EVERYONE. So please, let's help stop the misconceptions and support those who need our help."

Lastly, my dad openly fought depression his whole life, both in general and his own. No matter what anyone says, it is a FIGHT. Fight on.

— Zelda Williams (@zeldawilliams) October 10, 2014

Zelda asserted the necessity for people to speak up about mental illnesses, saying: "No matter what the misinformed say, you can't simply CHOOSE to make mental illness go away. It is NOT cowardly to suffer or seek help."

The Detention star concluded by remembering her father's own battle with depression.

"Lastly, my dad openly fought depression his whole life, both in general and his own. No matter what anyone says, it is a FIGHT. Fight on."

Robin Williams committed suicide at the age of 63, leaving behind his wife of three years, Susan Schneider, and his three children Zachary Pym, 31, Zelda Rae, 25, and 22-year-old Cody Alan Williams.