Mandy Moore Introduces Sterling K. Brown to Her Son Gus and 'This Is Us' Fans Are Swooning

'My two sons,' Moore captioned her sweet post.

Mandy Moore is introducing her real-life kid to her TV son! The 37-year-old actress took to Instagram on Thursday to share a pic of her baby boy, Gus, meeting Sterling K. Brown, who plays Moore's son on This Is Us.

In one of the adorable pics, Moore is in her age-progressed makeup on the This Is Us set, to play the grandmother version of her character, Rebecca Pearson, as Brown holds baby Gus to his chest.

Moore is clearly touched by sweet moment, as she looks off camera with a smile and a hand on her heart.

The second pic features Brown, who plays Randall Pearson on the show, holding Gus, while Moore rests a hand on her son's head.

"My two sons," Moore captioned the pics.

"What a sweet, sweet boy!!!" Brown commented. "Motherhood looks good on you, Momma!"

Moore and her husband, Taylor Goldsmith, welcomed their son in February. A month later, Milo Ventimiglia, told ET that he and the other cast members were all "excited" to meet the tot.

"Mandy and Taylor are just the most lovely people, and the kind of people you want to be parents, raising someone, especially considering what the world is. Knowing they're in charge of someone that will make a huge impact, hopefully, in the world, it's exciting," he said. "I'm just super excited [to be] supporting the two of them... Whatever the kid needs for the rest of their life, I'll be there."

"As I understand it from other friends who have kids, it's like the second your baby's born your world changes, you are at that point now living for that new life. So I imagine things have changed for Mandy," he added. "But, for me, Mandy's still the same she's always been, a wonderful person. She's always been a wonderful friend. She's always been an incredible talent in front of the camera. For me, I see the same thing, her life is just a lot bigger now with Gus around."