The actor, who shot to fame playing Will Smith's cousin Carlton in the iconic sitcom, welcomed his first child with wife Angela, 32, over the weekend.
Little Alfonso Lincoln Ribeiro Jr. was born at 10.45am local time in California on Sunday, 27 October, weighing 7lbs 10oz.
Breaking the news via Twitter, Alfonso, 42, wrote: "We are so blessed."
Angela added on her own account: "Absolutely loving the first 24 hrs with our new baby boy. He is healthy and beautiful...incredibly blessed."
Alfonso and Angela announced their first pregnancy back in May by tweeting childhood pictures of themselves alongside the caption: "Coming This Fall: A Baby Alfonso or A Baby Angela!"
The couple married in a sunset California ceremony in October 2012 in front of friends and family including Alfonso's eleven-year-old daughter from a previous relationship.
They celebrated their anniversary on 13 October, with both tweeting sweet messages of love. Alfonso wrote: "Happy Anniversary to my love @angiesue224. A year ago she made me the luckiest man in the world." Angela added: "1 yr ago today = happiest day of my life. So blessed. Happy Anniversary to the love of my life @alfonso_ribeiro."
Congrats to Alfonso and Angela!
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