Anthony Rapp Reflects on the 'Life-Changing' Deaths of His Mother and Rent Creator Jonathan Larson

Richard Corman

Anthony Rapp is revisiting his past nightly in his new Off-Broadway musical Without You.

Based on his 2006 memoir of the same name, Rapp — who originated the role of filmmaker Mark Cohen in Jonathan Larson's hit musical Rent — looks back on the deaths of Larson in 1996 from an aortic dissection at age 35 and his mother in 1997 from cancer at age 55.

"These two profoundly life-changing and impactful events happened at the same time," he tells PEOPLE.

Larson, the groundbreaking Broadway composer whose Rent changed the landscape of contemporary musical theater, died suddenly hours before his rock opera — based on Giacomo Puccini's classic La Bohème — would begin public performances in downtown New York City. Rapp's mother, Mary Lee Baird, died the following year.

"It's very tough. It's painful, but it's also really part of life," says Rapp, who adds that musicalizing his memoir for the stage has "been a long time coming."

RELATED: The True Story of Rent: How the Cast Banded Together After Creator Jonathan Larson's Death

Richard Corman

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Since Rent debuted in 1996, Rapp went on to star on Broadway as Charlie Brown in You're a Good Man, Charlie Brown, reprise his performance as Mark Cohen in the 2005 film adaptation of Rent and reunite with his former costar Idina Menzel years later in If/Then.

He credits much of his success to his supportive mother.

"On a very selfish personal level, I get to spend time with my mom in the show. I get to talk to her, and she talks to me in the show, and I get to spend time with Jonathan in the show and friends that I did Rent with," he says. "So I'm spending time with some of the most important people in my life that I've loved the most."

Richard Corman

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While the 51-year-old actor and new father is expecting some of his Rent costars to attend the musical's limited engagement at Off-Broadway's New World Stages, he notes that "it may be really hard for them" to revisit the past.

"There are some painful memories that are part of it," he explains. "It was joyful, but it was also painful. In some ways it might be hard to think about it. And I respect that."

For him, however, the process of writing 2006's Without You and subsequently developing it into a stage production has been "healing" — even if a profound loss is something one will never truly "get over," he says.

"Experiencing and honoring the loss of someone is also allowing for the missing of them, the recognition of what's gone, the recognition of what's still there — just the whole of it," he explains. "That's all part of healing too."

In his musical Without You, Rapp intertwines songs from Rent along with original tunes of his own, some that memorialize profound memories.

"The moment that my mom died, and I was with her body, it was an incredibly intense moment. And I thought, well, it's musical theater, so maybe that moment should be musicalized," he says, adding that he also set to music a letter from his mother written to him before she died.

"She wrote [these words] 26 years ago, and they still echo through the years," he explains. "The music helps it take on an almost ethereal feel."

Richard Corman

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

Performing Without You at this particular time in his life has also been special. He and fiance Ken Ithiphol recently welcomed baby Rai Larson Ithiphol on Dec. 2.

"This energy right now that I'm bathing in with my mom, I feel like it's osmosis coming through to him, I hope. It's very meaningful," he tells PEOPLE. "I'm not quite feeling tremendous grief right now about the fact that she's not here to meet him. I feel like she kind of is here."

Without You plays a limited engagement at New World Stages through April 30.