Anthony Rapp Welcomes Baby Boy Rai Larson with Fiancé Ken Ithiphol: 'Our Family Has Grown!'

Anthony Rapp is a dad!

The Star Trek: Discovery star, 51, and fiancé Ken Ithiphol welcomed their first baby via surrogate on Friday, introducing their Instagram followers to newborn son Rai Larson on Monday with their first family photo.

"Ken and I are thrilled to share that our family has grown!" Rapp started in the caption.

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"Our son, Rai Larson Ithiphol, was brought into the world on Friday, December 2, 2022, by an incredibly generous surrogate, to whom we are eternally grateful. (Rai is pronounced like 'rye' or 'chai.')" he wrote. "We love him very much."

They were met with an outpouring of love in the comments section from friends and fans. "Congrats!!" wrote Rapp's Star Trek costar Ethan Peck. "HALLELUJAH !! Welcome home, Rai!" his fellow Rent original Broadway cast member Daphne Rubin-Vega commented. "Congratulations!!" Lauren Lapkus wrote.

The proud parents announced their engagement in November 2019 after Rapp popped the question to Ithiphol, a leadership coach, social researcher and advocate, following nearly four years together.

"So something happened tonight. I asked @teerakeni if he would marry me and he said yes. I am so very happy and I'm so very thrilled to share this news," he wrote on Instagram at the time.

Rapp's exciting family news comes after he announced last month that he has another baby on the way, in the form of his Off-Broadway rock musical adaptation of his 2006 memoir Without You: A Memoir of Love, Loss, and the Musical Rent, premiering Jan. 14 at New World Stages.

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The show recounts his relationship with his mother at around the time he made his Broadway debut in Rent back in 1996, featuring music by Rapp and his late pal and Rent creator Jonathan Larson.