Marlon Wayans Shares His Reaction to Learning His Child Was Trans: 'I Grew the Most That I Ever Did' (Exclusive)

Marlon Wayans isn't the same dad he was a few years ago.

The hit comedian, actor and father of three, 51, is back with a new standup special, Good Grief, premiering June 4 on Amazon Prime.  It’ll be his fourth special amid a fairly recent foray into standup, with most of his sets based on personal experiences, like his journey to understand and embrace his son, who is transgender.

“I’m very vulnerable nowadays onstage," he tells PEOPLE in this week's issue. "I don’t know why it took me so long to do standup. Now I can’t stop.” Mostly, he’s found healing in the humor: “That’s my therapy. Life happens, and I go, ‘What’s funny about it?’ I’m literally trying to rescue myself.” 

When it comes to fatherhood, he's dad to sons Kai, 24, and Shawn, 22, with ex Angela Zackery, and daughter Axl, 18 months with ex Brittany Moreland. Wayans says he was thrust into a period of soul-searching when his oldest, Kai, first revealed they were transgender.

Marlon says he went through his own transition “from defiance to acceptance. It took me all of a week, and in that week I grew the most that I ever did in my life. You understand the purpose of kids and the beauty of unconditional love. At the end of the day, in my heart, only thing that matters to me is that my child is happy.”

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He has since relayed that experience to audiences in his standup “to gift not just laughter but some lessons.” And his son was okay with that. “I have a contract with my kids: ‘Whatever you do in life, just know that there’s a possibility I’m going to find some humor and talk about it,’ ” Marlon explains.

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One thing not on his joke list right now is his relationship with ex Brittany Moreland, with whom he’s currently in a custody dispute over their 18-month-old daughter Axl. “I don’t do public battles,” he says. “You don’t have to be together to let your child grow up in peace. Every child deserves that.”

As for his comedy, he's hoping the lessons in his jokes resonate with audiences.  "I feel like it was important for me to once again find the light in the darkness," he says, "and gift that to the audience because I feel like there's so many people that are going through it."