Robin Williams' son Zak is a new dad: 'We are beyond thrilled'

June 13 (UPI) -- Robin Williams' elder son, Zak Pym Williams, is a new dad.

The 36-year-old entrepreneur and his fiancée, Olivia June, announced in an Instagram post on June's account Wednesday they welcomed a baby boy May 22.

Williams and June named their son McLaurin, which was Robin Williams' middle name. June, the founder and CEO of the Vina app, shared a slideshow of family photos taken by Williams' sister, Zelda Williams.

"Introducing you to my little family! My fiancé, Zak, and I were so happy to welcome baby McLaurin to the world on May 22nd. We are beyond thrilled he chose us to be his parents, and obviously think he's the best, smartest, and cutest baby ever!!" June wrote.

"We've kept this news private for a number of reasons, one of which is my increasing emphasis and appreciation for living life away from social media and focusing on my offline relationships, another being the challenges that face us as women startup founders," the new mom said.

"I'm excited to be expanding my role from global change-maker startup CEO, connecting millions of women to their best friends, to a milk factory, raising a really amazing little man who has a boss mamma," she added. "None of this would be possible without the most incredible and supportive partner a woman could ever hope for."

Zelda, 29, an actress who has appeared on Dead of Summer, Criminal Minds and Jane the Virgin, also shared the news in a post on her own account.

"News is finally out: I'm an auntie!" the star confirmed. "Meet Mclaurin Clement Williams, aka Mickey, aka Dr. Baby!"

"He's a squishably cute pterodactyl cooing tiny wonder and I love him so much already," she said. "Big shoutout to Mickey on being the fastest swimmer, and huge congrats to @heyoliviajune and my big bro @zakpym on creating this little joy (and poop) factory!" she added.

Robin, who died by suicide at age 63 in August 2014, was parent to Williams with Valerie Velardi and to Zelda and son Cody with Marsha Garces. Zelda shared her pain in a post in July ahead of what would have been the actor's 67th birthday.

"Everyone who has dealt with loss knows the pain of certain anniversaries, moments full of memory that come round like clockwork and usurp all others, no matter how hard you may try to prepare for them," the actress wrote.

"Happy early birthday, poppo," she said. "Miss you every day, but especially these ones."