Sterling K. Brown Shares Sweet Photos of Sons Andrew and Amaré's First Day of School

Sterling K Brown/Instagram, Miikka Skaffari/Getty

Sterling K. Brown is reflecting on one of parenting's bittersweet moments.

On Wednesday, the This Is Us alum shared a photo of sons Andrew, 11, and Amaré, 6, posing together while sitting on a stoop. The two boys look handsome in polo shirts, shorts and sneakers with big smiles.

In the caption, the actor recalled a comment his mom would make while he was growing up and his new understanding of it as a parent himself.

"When I was a kid, my mom would frequently say '18 years goes by real fast.' I think she knew that once I graduated, life would take me someplace other than home," he wrote.

"And there was joy for what the future would hold, but also a bitter sweetness in knowing that our time under the same roof would be limited. Today, is the beginning of 6th grade and 1st grade. And I know exactly what my mom meant! #TimeFliesWhenYoureSurroundedByLove❤️"

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In December, Brown shared photos from some quality father-son time together at a football game.

Posing for a selfie with his sons in their seats, he wrote, "Chiefs are in town…I ain't scared!! #BoltsUp"

Earlier in the season, Brown, Andrew and Amaré posed proudly in SoFi Stadium as the actor declared he and his kids were officially Los Angeles Chargers fans.

"For a long time I've been a man without a team. I am proud to report that is no longer the case. Me and my kids get to root for their home town team…& I couldn't be happier!"

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Brown thanked his two sons at the 75th Annual Golden Globes in 2018 when he took home the award for best actor in a television series, drama — becoming the first black actor ever to do so.

During his acceptance speech at the award show, Brown made a point to thank his wife, Ryan Michelle Bathe, after he had previously been cut off at the 2017 Emmy Awards during his acceptance speech just as he was about to thank her.

"I don't want to run out of time. Let me thank my wife. I love you so much, thank you for supporting me so much. My kids, Andrew and Amare, Daddy loves you," Brown said, before promising to "take you to school in the morning."