Jessica Simpson's Daughter Maxwell Drew Is "3 Going on 13" in New Photo

Simpson and husband Eric Johnson are also parents to son Ace Knute, 2

Well, someone can't wait to grow up...

Jessica Simpson posted on her Instagram page Saturday a photo of her and husband Eric Johnson's eldest child, daughter Maxwell "Maxi" Drew, looking adorable in an oversize, fancy, dark fur coat...possibly her mom's.

"3 going on 13 #MAXIDREW," Simpson wrote.

Simpson, 35, and Johnson, 36, are also parents to son Ace Knute, 2. Simpson has often posted pics of their kids on social media. Last week, she shared a cute pic of their daughter teaching her how to pose.

Ace and Jagger #COUSINS

A photo posted by Jessica Simpson (@jessicasimpson) on Jan 31, 2016 at 5:21pm PST

Also last week, Simpson shared a photo of Ace holding his new baby cousin, Jagger Snow Ross, daughter of the star's sister Ashlee Simpson-Ross, 31, and husband Evan Ross, 27.