Sally Field's Son Recalls How His Coming Out Experience Inspired Mom's 'Brothers & Sisters' Storyline

Sam Greisman is a New York-based writer and the youngest of Sally Field's three children. (Her other two sons are Peter Craig, 53, a screenwriter and novelist, and Eli, 50, a writer and director.) Here, exclusively for PEOPLE, Greisman opens up in an essay about what Field has taught him — and, in her most vulnerable moments, shown him.

I've always been a momma's boy — painfully, occasionally ashamedly so. Perhaps too obsessed with her. Maybe it's because I'm the youngest, by sixteen years. Maybe it's because I was a shy little kid and my mom was a safe space; a hip I was attached to.

Maybe it's because gay men feel a certain undeniable affection for award-winning actresses. Who knows! Whatever it is, we have always been incredibly close.

I remember a nightmare I had when I was around seven. I ran into my mom's room crying because I dreamt that she wasn't there to pick me up after school; I'd looked everywhere and couldn't find her. Awake andpanicked, I sat on her bed as she said: "Sammy, I will always be there to pick you up, even when I'm not there."

For the next few years I had to consistently call out "goodnight" from my bedroom at different intervals as I fell asleep, afraid that when she turned the lights off she would disappear somehow. I needed to know she was still there.

I grew up so connected to my mom that I can trace my life through her career. While she shot Mrs. Doubtfire, I built model airplanes and hung them all over our rented house in San Francisco. During Forrest Gump, I would get to buy something at the toy store in Beaufort, S.C., if I slept through the night without a pacifier. I fell in love with New York while she was on Broadway in The Goat. The first week of shooting on Brothers & Sisters was rearranged so that she could move me into my dorm at NYU. (Later, a frank, heartfelt conversation about my queerness was used verbatim for a scene between her and Matthew Rhys. Still waiting on a retroactive writing credit on that, if I'm being perfectly honest.)

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I was in my final semester of college when I told her that she was right, she had to make Steven Spielberg at least give her a screen test for Lincoln. I was on my best friend's couch as she called me to tell me she got the part. And, a year and a half later, at dawn, on a rainy morning in L.A., I scrambled out of my room and banged on her door to tell her she had been nominated for a third Oscar.

"Congratulations," I said. She hugged me. "I did it, Sammy," she whispered. Though my mother has always been my protector, it's moments like those that have been the greatest gift. To see her as more than "my mom," chances to see her as her own person, with her own wishes and desires and vulnerabilities.

She has given me the chance to see her as a woman and an artist, always striving to be better, always looking around the next bend, willing to be vulnerable. She's taught me what it means to have passions, how to dedicate yourself to a craft — to be willing to care, no matter how much you achieve, even if it breaks your heart.

My mom has given me permission to be messy, to struggle, to fight with her, to rage at her when I have no one else to yell at, given me permission to pick out all of her award show dresses, because... well, no explanation needed.

She has taught me that life, like art, is about picking yourself up and dusting yourself off, like she has done countless times. And luckily for me, I know that when I fall she will be there to pick me up. Even when she's not there.

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