The former American Idol contestant, who came second in the show's fourth season, announced on his website that his first daughter was born on Monday.
"Bo and [his wife] Caroline welcomed Merrin Elizabeth Joy Bice, on April 23, 2012," the message reads. "Merrin was a healthy 8lbs 11 oz.
"Both Mum and baby are doing great!"
Bice already has three sons - Adain, Caleb and Ean, who was born in January 2010.
The message on the website described the boys as "proud big brothers" to their new baby sister.
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