Jessa Seewald from "19 Kids and Counting" had mixed feelings of happiness and sadness after her sister Jill and her husband Derick Dillard, together with their firstborn son Israel David, left the United States on Monday to embark on a new ministry overseas.

On one hand, Jessa is happy that the Dillard family will be serving God on an even bigger mission field. But on the other hand, she is pretty bummed that her elder sister has moved far away from home.

On her Instagram account (@jessaseewald), Jessa shared a photo of Derick and Jill walking side by side with Israel David in tow. The Dillard family were just a few steps away from boarding a plane when she posted the photo.

"So excited for @jillmdillard & @derickdillard! They've been praying about and working towards this transition since late last year, and are so excited to finally be heading to the mission field! Please continue to pray for them! ❤️ And be sure to check out their blog at www.dillardfamily.com," she captioned the photo.

Jessa then shared the Bible verse Mark 16:15 which says, "Go into all the world and preach the gospel to every creature."

The Dillard family did not reveal where they would be doing missionary work, citing security concerns, but a lot of people have speculated that they will be heading back to Nepal, where Derick worked as a missionary for two years before he officially met Jill. Back then, Jim Bob served as Derick's prayer partner and it was actually the "19 Kids and Counting" patriarch who suggested that Derick and Jill will make a great match because they have so many things in common.

"We have a deep love and care for all of the world and a real passion for those in the nations, as many have even seen in the early stages of our relationship," Derick wrote in the Dillard Family Blog. "Our hope is that all peoples of the world would come to repentance and put their hope in the Lord, Jesus Christ."

Before the Dillard couple and their son left on Monday, the Duggar family posted a homemade video of their final moments together.

The emotionally charged home footage showed the family breaking down in tears. Even the unseen camera operator could be heard sobbing in the background.