"We are open to the idea of adoption," Michelle, 45, tells PEOPLE. "We are praying about it, and we will see what God has in store. Love for children has been placed on our hearts."
The ever-expanding crew – eldest son Josh, 25, and his wife, Anna, 24, just recently announced they are expecting their third child in June – were moved by a visit to an orphanage in China on their recent trip there.
The visit to Beijing was filmed for TLC's special 19 Kids & Counting: Duggars Do Asia, which airs Tuesday (9 p.m. ET) on TLC. Watch an exclusive clip below.
"The kids are definitely pushing towards wanting us to open our home up to another child or more," says Michelle. "They see how much we have been blessed with and how little so many children have and they want to share. We tell our children that would have to be something that is God's will for our family, and we will see if it is. Our children love children, and we all do."
Though Michelle and Jim Bob, 45, lost their last pregnancy – a girl they named Jubilee – to miscarriage in 2011, Michelle says, "We are open to whatever is in store. It doesn't really matter whether I would have another child or we would adopt, but we want to approach it with an open heart."
She adds, "We have friends that have adopted children who are a great influence in our lives, and we have talked about their experiences. So it's something we've considered. We have to know for sure that is what God wants for us to do."
"When he gives us a child [through pregnancy], there is no doubt in our minds that is what He wants, but when it comes to adoption, we would have to know for sure that was His will."