“Wow didn’t u just have a baby John smh go take care of it !!!!!! disgusting,” Teigen, 32, hilariously tweeted along with a photo of the new dad, 39, on TV during an interview at Sunday’s Billboard Music Awards in Las Vegas.
Legend, who is performing “A Good Night” during the awards show, also revealed the special significance behind his second child’s name.
“We named our first daughter Luna Simone Stephens; every name we give to our kids I think will have a little bit of musical history to it. So Miles is, of course, is the same name as the great Miles Davis,” the Grammy and Oscar-winning artist told E!’s Jason Kennedy on the carpet.
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As for the baby boy’s middle name, Teigen had a say in choosing the moniker.
“Chrissy really liked the name Theodore, so we put it all together as Miles Theodore Stephens. When he came out and we hung out with him for a little while we were like, ‘Yeah, he looks like a Miles,’ ” Legend explained.
Check out PEOPLE’s full Billboard Music Awards coverage to get the latest news on music’s big night.
During Legend’s performance, Teigen shared a video of herself cooking and captioned it “hello it’s shortrib night be home by 9.”
Just three days since Miles Theodore’s birth, the father of two shared that the Teigen/Legend household couldn’t be happier.
“We’re so excited to have him in the family now. Luna’s excited, Chrissy’s excited, I’m excited. It’s nice to have our little family of four now,” he said.
The inspiration behind Miles Theodore’s name comes hours after the couple shared the first photo of their baby.
“Hello, world! This is Miles Theodore Stephens – We are drowning in his little peeps and nuzzles,” wrote the proud mom. “Our household feels overwhelmed with love. Thank you for all your well wishes!”
RELATED VIDEO: Chrissy Teigen and John Legend Share Their Son’s Name and Introduce Him in Adorable First Photo
“Same nose!” wrote the Lip Sync Battle star of the siblings. “He is a few weeks early so he’s litttttttle and makes the teeniest noises. We are in love.”
The 2018 Billboard Music Awards are broadcast live on NBC from the MGM Grand Garden Arena in Las Vegas on Sunday, May 20 at 8 p.m. ET/PT.