Aww! Jessica Simpson's little girl is growing up so quickly! The Fashion Star mentor, who is currently pregnant with her second child, couldn't resist sharing an adorable snapshot of her daughter Maxwell Drew on Twitter on Friday, Feb. 1.

"My lil dollface is 9 months today!" Simpson captioned the shot. In the photo, the singer's precious firstborn, clad in a tiny navy, red and white-striped sweater and snug jeans, looks awestruck as she balances precariously inside a sink.

PHOTOS: Jessica Simpson's maternity style

Maxwell (whose papa is Simpson's fiance Eric Johnson) even shows off a full head of blonde hair, just like her mom.

Simpson, 32, initially confirmed her second pregnancy on Christmas Day, with a shot of Maxwell sitting on a beach with the words "Big Sis" written in front of her in the sand. Us Weekly revealed the news just one month earlier, on Nov. 28.

PHOTOS: Maxwell Drew's baby album

"Merry Christmas from my family to yours!" she captioned the shot. Simpson's second pregnancy "definitely wasn't planned," a friend told Us at the time, though she "loves being a mom and "is overjoyed."

And Maxwell's younger brother or sister couldn't be born into a more caring family, Simpson's younger sister Ashlee Simpson revealed to Us recently.

PHOTOS: The Simpson sisters through the years

The 28-year-old mom, who is shares son Bronx, 4, with ex Pete Wentz, told Us that her little boy is protective of little Maxwell, and will likely be the same for Jessica's second child. 

"He is definitely protective, and he's so excited about every time she's growing," Ashlee told Us about his excitement over little cousin Maxwell. "He loves that stuff!"

This article originally appeared on Jessica Simpson Daughter Maxwell Drew, 9 Months, Stands in Sink in Adorable New Picture