Jessica Simpson shared a picture of daughter Maxwell and son Ace on her Instagram on May 6. Credit: courtesy of Jessica Simpson

Mini models! Jessica Simpson's beautiful children are her favorite Instagram subjects. Daughter Maxwell Drew, 2, and son Ace Knute, 10 months, are frequently featured on the fashion designer's social media page, and early Tuesday, May 6 she posted a picture of the pair clad only in diapers. 

"Diaper buddies," she captioned the adorable shot. 

Maxwell recently celebrated her second birthday with a screening of Rio 2 in theaters, while parents Simpson and Eric Johnson enjoyed a date night at the White House Correspondents' Dinner on Saturday, May 3. 

Little Ace is used to posing for his mom's pictures by now. A few weeks ago she posted a photo of him in the bathtub with pal Cacee Cobb's son Rocco

"Bunny Babies #aceandrocco," she captioned the picture.