“My two favorite laker fans,” the Maroon 5 frontman, 37, captioned the snap, along with a baby, bottle and basketball emojis.
The Victoria’s Secret Angel, 26, showed off her baby bump in a scalloped red bikini, lounging by the pool in a Los Angeles Lakers hat and flashing a peace sign for the camera.
In March, PEOPLE confirmed that the couple, who wedded in Los Cabos, Mexico in July 2014, were expecting. Prinsloo has been showing a hint of her growing bump in a series of outings lately, including on Monday with the mom-to-be in a fitted, patterned maxi dress.
The model also acknowledged the happy news by posting a painting of a pregnant woman on her Instagram on Thursday.
This will be the first child for both stars, though The Voice coach says more are not out of the question.
“I want to have 100 kids,” Levine said in 2014. “I want to have more kids than is socially responsible.”