The singer revealed the news by showing off her baby bump in a sweet Instagram post on Tuesday.
"Here’s the other half of what I’ve been creating this year," Platten wrote, alongside a beaming mirror selfie in which she's cradling her stomach while wearing a sunny, billowing summer dress and white boots.
"Baby #2 coming in hot," she added. "This was a hard secret to keep."
This will be baby no. 2 for the "Fight Song" singer and her husband, Kevin Lazan. The couple are parents to a 2-year-old daughter, Violet Skye, whom they welcomed in January 2019.
Several of Platten's fans and famous friends celebrated the news with supportive comments, congratulating her on the announcement.
Singer Jewel excitedly exclaimed, "Woooot!!!!!" with several heart emoji, while LeAnn Rimes commented sweetly, "Awww... congrats, beauty." Paralympian and former Dancing With the Stars runner-up Amy Purdy shared, "Ahh look at you cute mama!"
On Tuesday morning, Platten joined The Talk as a guest host, and revealed her pregnancy during the show.
"I realized when I got asked to do the show today, I was like, 'I haven’t announced this yet. I guess I’m going to have to announce this,' she said, laughing, after standing up to show off her growing baby bump. "So, this is my announcement!"
Her fellow Talk co-hosts actually surprised Platten with an adorable baby present -- a special onesie with The Talk's logo on the front.
"This is the first baby gift I’ve received for this baby," the singer said, moved by the sweet gift. "The second baby, everybody always says, 'Oh, you’re fine! You have everything.'"
After opening the present, Platten was touched by the heartfelt gesture. "Thank you guys so much. That is so, so meaningful. I appreciate it," she shared.
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