The pregnant 28-year-old model captured a cute picture of Levine and 14-month-old Dusty Rose's bare backsides that she shared with her 5.2 million Instagram followers.
The snapshot shows Levine holding Dusty's hand as he appears to lead her to a bubble bath. Prinsloo covered her family's behinds with peach emojis.
"Same butt different," she captioned the photo.
Prinsloo and Levine welcomed Dusty in September 2016, and announced this September that they're expecting their second child. Levine confirmed in an interview this month that Prinsloo is pregnant with another daughter.
"It is a girl," the 38-year-old singer said on The Ellen DeGeneres Show.
"She's awesome," he added of Prinsloo. "Hs'e just, like, a champion of the world. She's killing it. You wouldn't know she's almost seven months pregnant."
Prinsloo had showed off her baby bump ahead of the 2017 InStyle Awards in October. She posted a photo of herself wearing a form-fitting minidress that highlighted her growing belly.
"Got myself out of my maternity jeans just to celebrate the very talented @hungvanngo. LOVE YOU, you deserve it all. Thanks @instylemagaine for a beautiful dinner," the model wrote.