"I miss you every day." Zelda Williams' touching tribute to her father on his birthday.

Robin Williams would have turned 67 this weekend.

The legendary actor died in August 2014 after an intense battle with a pernicious neurodegenerative disease that was slowly eroding his mind.

In honour of his birthday and the upcoming anniversary of his death, Williams’ daughter, Zelda, has posted a tribute to her dad on Instagram.

“It’s that time of year again. Everyone who has dealt with loss knows the pain of certain anniversaries, moments full of memory that come round like clockwork and usurp all others, no matter how hard you may try to prepare for or avoid them,” she wrote.

We remember the legend that was Robin Williams…

The 28-year-old explained that these weeks were always the hardest for her, and she tended to retreat from the public gaze in order to process her feelings.

The actress added that she always finds it difficult when well-meaning people tell her how much her dad meant to them.

“It’s harder still to be expected to reach back. So while I’ve got the strength, consider this my one open armed response, before I go take my yearly me time to celebrate his and my birthdays in peace,” she wrote.

Williams then thanked her fans for loving her dad and supporting her family as they grieve.

“Thank you for loving him. Thank you for supporting him and his life’s work. Thank you for missing him.

“Mostly, try to spread some laughter and kindness around. And creatively swear a lot. Every time you do, somewhere out there in our vast weird universe, he’s giggling with you… or giving a particularly fat bumblebee its wings.”

Williams ended her post with a message to her dad, “Happy early birthday, Poppo. Miss you every day, but especially these ones”.

On August 10, 2014, Williams said goodnight to his wife Susan and retired to his room.

A post shared by Zelda Williams (@zeldawilliams) on Jul 19, 2018 at 1:04pm PDT

“As we always did, we said to each other, ‘Good night, my love’, ” Susan explains in the new biography, Robin.

“He seemed like he was doing better, like he was on the path of something.”

The next morning, Susan discovered Williams had taken his own life.

Three months later the autopsy revealed the veteran comedian had been suffering from “diffuse Lewy body dementia”.

He wasn’t depressed and he didn’t have Parkinson’s – an incurable brain disease had slowly robbed Williams’ of his life force.

“It was not depression that killed Robin,” Susan told People. “Depression was one of let’s call it 50 symptoms and it was a small one.”