Marcia Gay Harden Opens Up About Her Mother's Battle with Alzheimer's and Facing Its 'Scariest First Moments'

Marcia Gay Harden clearly remembers the first time she realized her mother might be suffering from Alzheimer’s disease.

“Eight years ago, we were on a trip and my mom kept forgetting where she had put her passport,” Harden tells PEOPLE. “At first I thought, Okay, I do that sort of thing all the time,’ So she did it one time, okay, but two times, then three and four. Then you go, Oh, something is not right here.’ ”

Harden and her siblings soon took their mother Beverly, who was 72 at the time, to the doctor, where she was officially diagnosed.

“I think one of the most important things to do when dealing with this is that the family be very cohesive and that the person with the disease be active in describing what they want their future to be,” says Harden.

To help raise awareness, the Oscar winner, 57, is joining forces with the organization Notes to Remember and Biogen to spread the word about the early signs of the disease.

“This campaign struck me to the heart because it is about the scariest first moments,” says Harden.

The actress, who most recently played Christian Grey’s mother in Fifty Shades Darker and starred on How to Get Away with Murder, is currently writing a loving memoir about her mother and their bond.

“My mom and I are two peas in a pod. We’re very, very similar. She, I’m proud to say, is an artist. She was a great traveler, and she was a very hands-on mom like me,” says Harden, a mother of three.

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The actress admits that dealing with a family member with Alzheimer’s can be very challenging, and she hopes that by sharing her personal story, she can help others in the future.

“I can be quiet about it but I don’t see how that helps anybody,” she says. “It’s important to me to be a part of the future, a part of the hopeful tide, which will help to eradicate the disease. That’s my prayer, that’s my hope.”

This article was originally published on PEOPLE.com