Laura Dern Celebrates 'Amazing and Kind' Son Ellery on His 21st Birthday with Rare Photos

lauradern/Instagram

Laura Dern's son is all grown up!

Earlier this week, the Big Little Lies actress shared one throwback photo and one more recent shot with son Ellery on Instagram in celebration of his 21st birthday.

"Greatest gift I could have ever dreamt up," Dern, 55, said of her son in the caption. "Happiest 21st birthday to you my amazing son/friend/inspiration. You teach me every day…about art..empathy..and grace."

"You are a profound human and artist. And you are such a kind and amazing man. I'm so blessed and lucky to love you and learn from you. And you make me laugh every day," she concluded the sweet post.

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RELATED: Laura Dern Celebrates 'Amazing' Son Ellery's High School Graduation: 'My Boy's Day!'

Dern shares Ellery and 17-year-old daughter Jaya with ex-husband Ben Harper.

On a March episode of The Ellen DeGeneres Show, Dern said that she's proud of Ellery for keeping family traditions alive with music, noting that he's a third-generation musician after his dad and grandparents.

Dern also opened up about Jaya's ambitions to become an actress, telling host Ellen DeGeneres that she's excited for Jaya to eventually be the family's third generation of actors following herself and her parents Diane Ladd and Bruce Dern.

"There is something very moving about it," she explained. "Jaya's 17 and I started very young at 11 but I'm so happy that she's waiting and wants to go to school but really knows in her heart she wants to act."

Laura Dern/Instagram Laura Dern with her parents and kids

"And maybe if she does, we'll end up having the privilege of working together," Dern added.

"I'm basically making her wait," she admitted, noting that she "saw the consequences of not being in school" and having a normal childhood.

Last September, Dern celebrated her firstborn on Instagram, writing, "National Sons Day! What a blessing just to get to share the love for our boys!!!! My life grows more full with every day getting to walk alongside you, my boy."

Before that, to honor Jaya, the proud mom wrote in another post, "Love being with my inspiration on National Daughters Day!" alongside a mother-daughter selfie.