The latest, Johannah Faith, weighed in at seven pounds, six ounces when she was born Tuesday.
Michelle says Johannah may not be the couple's last child.
"I would like more, but we will wait and see," she tells The Early Show co-anchor Hannah Storm. "I always say we'll just take it one at a time. … But I would love more. They're so precious, such a blessing."
Johanna is "wonderful," Michelle says. "She is just precious in every way. We are enjoying little Johannah."
She is the Duggars' first girl in eight years. In the interim, they added six boys to the family.
"It's really fun to do pink ruffles and lace again," Michelle says.
How do Michelle and Jim Bob keep the kids straight?
"Sometimes," Jim Bob says, "we go to call one, and just start at the top and work our way down. But Michelle is actually very organized, and she does a very good job of keeping everything together."
The Duggars use a buddy system to get by.
Their eldest, Joshua, 17, says that entails each sibling taking on a younger one and seeing to it that their day-to-day activities are taken care of, including lessons. The Duggar children are home-schooled.
Joshua is helping his dad build a house.
The current Duggar abode is less than 2,400 square feet, with three bedrooms and one washer and one dryer. Their new home will be about 7,000 square feet, with nine bedrooms, four bathrooms and a commercial kitchen.
"Just a lot more space for everybody," Jim Bob says.