"We just found out we're having a girl officially! I knew it! Only a girl could cause this much drama with all this vomiting ha!" the first-season American Idol winner and former Duets celebrity partner tweeted at the time.
Clarkson, who had a difficult pregnancy with morning sickness, had predicted she was going to give birth to a daughter -- and firmly believed in her gut feeling -- but discussed gender-neutral names with Blackstock anyway prior to discovering the baby's sex.
"Honestly, the name we picked, if it's a boy or a girl, it's the same name," Clarkson told Ellen DeGeneres in early December of last year when she was 11 weeks pregnant. "You won't guess it. It's like a random name, [but] it's not like some weird famous person that's going to be like, 'Blue Jazz.'"
This is the third child for Blackstock, who has a son Seth and daughter Savannah from his previous marriage.
Clarkson announced on Twitter in late November she had a baby on the way. She wed Blackstock, a 38-year-old talent manager, in an intimate October 2013 ceremony at Blackberry Farms in Tennessee. The couple got engaged in December 2012.
Rumors had circulated Clarkson was pregnant around the time she got married because she had suddenly ditched her plans for a big fall wedding and ended up quickly having quiet nuptials in Tennessee.
However, the singer initially shot down the pregnancy speculation before hinting that may have changed during a late November appearance on The Tonight Show with Jay Leno.
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