The popstar, who is expecting her first child with husband Brandon Blackstock, spoke about her happy baby news and the release of her new Christmas album, Wrapped in Red, on US chat show, TODAY.
When asked about the sex of her baby, Kelly said: "I'm way to early to know. It's a gut feeling because she's killing me and of course, it's a girl right, who's causing the trouble?!
"I don't know why they call it morning sickness - that's my big joke right now," Kelly continued. "It's like all day and all night. I'm just looking forward to the second trimester. They say it's better."
Kelly, who married Brandon on 20 October in a romantic ceremony held at Blackberry Farm in Walland, Tennessee, has previously been open about plans to expand her brood.
The 31-year-old, who is currently stepmum to Brandon's two children from a previous marriage, announced her pregnancy via Twitter on 19 November.
Speaking about baby names with the show's host Savannah Guthrie, Kelly revealed that she and Brandon have already picked names for both a girl and a boy!
"We're not saying because I don't want someone to steal my baby's name," Kelly added. "We named our kid before we were even pregnant!"
Check out more stars who are expecting a baby in the gallery below:
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