The 34-year-old actress dedicated a sweet post to Ventimiglia on Instagram on the actor's 41st birthday Sunday.
Moore shared a playful photo of herself and Ventimiglia wearing mustaches on the This is Us set. The pair co-star as Rebecca and Jack Pearson on the popular NBC series.
"As remarkable as Jack Pearson is, this guy is even better," Moore captioned the post. "Happy Birthday, @miloanthonyventimiglia. Our job is so much fun because we get to do it together. Can't wait to get back to it. [Love] you, Mi!! #thisisus."
Ventimiglia thanked Moore and other well-wishers Sunday on Twitter.
"Grateful to be here (thanks Mom + Pop). Thanks for the birthday wishes all. Love each other, love always. MV," he wrote.
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