Jinger (Duggar) Vuolo has hit the four-month mark!

The Counting On star, 24, shared an Instagram update on her pregnancy over the weekend, showing off her baby bump in front of a sign revealing that she is 18 weeks along.

“Update on Baby Vuolo ” she captioned the shot, in which she posed with her side to the camera to provide a good glimpse of her growing belly.

“Baby is the size of a bell pepper” was also scribbled on the chalkboard with an illustration of the veggie.

The last time Jinger tracked her progress for her Instagram fans was at 15 weeks, when the baby was about the size of an apple.

Jinger and her husband Jeremy Vuolo, 30, announced in early January that they are expecting their first child together.

“The past fourteen months have been the best of our lives as we have had the wonderful privilege of beginning our journey through life together in marriage. We both looked forward to the joys of marriage but neither one of us fully understood just how amazing the start of this journey would be. Truly, the Lord’s mercies are new every morning!” the couple wrote on their website.

“Now, the journey has taken an exciting turn: we are expecting our first child!” they continued. “We are praising God for this beautiful gift and ask that you join us in praying for a safe and healthy pregnancy.”

While the Counting On couple has yet to find out what the sex of their child is, they both have an inkling that it’ll be a boy — though they’ll be “happy either way,” Jinger said in a TLC video that was released following their pregnancy announcement.

“I would love to have a little princess,” admitted Jeremy, who hopes their firstborn will be just like his bride.

“I am praying that the baby will look like, act like, talk like, be like Jinger, and so I’ve asked everyone else to pray as well,” he said with a smile. “I was a little terror as a child, so I’m hoping that the little one will be as much like Jinger as possible.”

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But Jinger isn’t the only one who will be entering motherhood — younger sister Joy-Anna is also pregnant with her first child with her husband Austin Forsyth, while younger brother Joseph and Kendra Caldwell are expecting their firstborn, a son.