"Alfonso Lincoln Ribeiro Jr. was born today at 10:45 a.m.," Ribeiro tweeted late Sunday. "We are so blessed. ... We also want to thank our amazing Dr. Jason Rothbart. He was so great and a calming influence in the room."
"They are all healthy, happy, and exhausted," the actor's publicist later told UsMagazine.com.
Afonso Jr. weighed in at 7 pounds, 10 ounces, and measured 21.5 inches when he was born, the celebrity news website said.
Ribeiro and Unkrich were married last October. Ribeiro also has an 11-year-old daughter, Sienna, with his ex-wife Robin Stapler.
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