The singer, actress and and fashion designer, who welcomed her third child, daughter Birdie Mae, two weeks ago, took to Instagram with a photo of a 5-ounce bottle teeming with the results of her pumping efforts.
"This is what success feels like," she wrote in the caption, adding a cow emoji.
Simpson, 38, and her hubby, Eric Johnson, welcomed little Birdie Mae on March 19, and the next day shared a photo of the newborn with the excited news of her arrival.
"We are so happy and proud to announce the birth of our perfect daughter, Birdie Mae Johnson," the proud mama wrote, adding that her baby weighed a robust 10 pounds and 13 ounces.
The couple are already parents to daughter Maxwell, 6, and son, Ace, 5.
During her rough pregnancy, Simpson was candid (and often hilarious) with fans about the many challenges she dealt with.
When she broke a toilet seat in February, she proudly shared a photo of the evidence, along with a warning to other expectant moms not to lean back on the toilet.
In early March, just days before welcoming Birdie, the singer revealed she'd been laid up for a whole week in the hospital with a bad case of bronchitis.
We're so glad things have finally turned around for Jessica!