Pregnant Jill Duggar and her sister-in-law Anna Duggar posed with their adorable baby bumps on Wednesday, Feb. 18 -- see the photo! Credit: Courtesy of Anna Duggar

So fun to be pregnant at the same as Jill! #babybumps #20weeks #34weeks #4Kids #1Kid #19Kids @jillmdillard

A photo posted by Anna Duggar (@annaduggar) on Feb 18, 2015 at 12:04am PST

Double the cuteness! Pregnant Jill Duggar and her sister-in-law Anna, also expecting a baby, posed with their dueling baby bumps in an adorable Instagram photo on Wednesday, Feb. 18.

"So fun to be pregnant at the same as Jill!" Anna, 26, captioned. "#babybumps #20weeks #34weeks #4Kids #1Kid #19Kids @jillmdillard." The relatives cradled their growing bellies while smiling ear to ear.

Anna and Jill's brother, Josh Duggar, announced in December 2014 that they are expecting their fourth child together. The couple wed in September 2008 and are already parents to daughter Mackynzie Renée, 5, and sons Michael James, 3, and Marcus Anthony, 20 months.

Jill, meanwhile, can probably learn a lot from her older brother. The 19 Kids and Counting star, 23, and her husband Derick Dillard, 25, are gearing up for their first little one. They married in June 2014 and announced their happy baby news just two months later.

Earlier this month, Jill was the guest of honor at a baby shower. Some of the items on her wish list included diapers, pacifiers, a fitness stability ball, and more unique items like Olive Garden and Subway gift cards.